4x4 Engage/Disengage Trouble, general info & Recall info:Help get Ford R/C F150GEM - F150online Forums

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4x4 Engage/Disengage Trouble, general info & Recall info:Help get Ford R/C F150GEM


Old 01-30-2002, 10:47 PM
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4x4 Engage/Disengage Trouble, general info & Recall info:Help get Ford R/C F150GEM

FORD has many related problems it REPORTS w/ the GENERIC ELECTRONIC MODULE (GEM) in the EXPLORER & the F250/350's. They have a factory recall on that part for those trucks.

I have a 97 f150 w/ the same problems & I'm reading about how others on this site w/ f150's have the same problem as well.

Do you think Ford has a Different type of GEM MODULE for the EXPLORERS & F2/350's or do you think FORD forgot about the 150's?

I called Ford's COUSTMER SERVICE SUPPORT LINE to inform them of my situation. They said they have not heard any complaints about F150 GEM's.

Do Your part if you have a 4x4 shift problem & call FORD at 1-800-392-3673

MORE INFO ABOUT 4x4 shift problems::::::::::::::

Ford recalls Explorers due to 4x4 lock ups & air bag problems
June 6, 2000
Ford Canada is recalling certain 1999-2000 Explorer because the generic electronic module (GEM) could experience a condition referred to as "lock-up."
This could cause a situation where the GEM controlled electronic functions (e.g., front windshield wipers, interior lights, 4x4 system, etc.) could not be turned ON or, in some cases if the function is ON, could not be turned OFF. An inoperative front windshield wiper system could adversely affect driver visibility.
18,576 sport utility vehicles equipped with 4.0L engines and All-time 4-Wheel Drive (A4WD) powertrains, sold in Canada between September, 1998 through September, 1999 are affected by this recall.
Dealers will install a resistor in the GEM circuit, which will prevent the electronic noise on the diagnostic link from affecting the GEM during vehicle operation. The manufacturer has reported that owner notification began April 15, 2000. Full information is available at Transport Canada's website <http://www.tc.gc.ca/roadsafety/Recal...sp?recno=8128&>.
Owners who do not receive the free remedy within a reasonable time should contact Ford at 1-800-392-3673.

Ford Recalls Certain 1999 Model Year F-250/350 Super Duty Series 4x4 Trucks - GEM Module Replacement Provided courtesy of Gabe Deno aka gdenoPSD -
January, 1999 To: All Ford and Lincoln-Mercury Dealers Subject: Owner Notification Program 98B29 - Certain 1999 Model Year F-250/350 Super Duty Series 4x4 Trucks - GEM Module Replacement OASIS - Yes OWNER LIST - Yes PARTS RETURN - Yes PROGRAM TERMS - Through July 31, 1999, Regardless of Mileage AFFECTED VEHICLES Certain 1999 model year F-250/350 4x4 Super Duty series trucks equipped with the Electronic Shift On the Fly (ESOF) option and produced at Kentucky Truck Plant from Job #1 through July 21, 1998. REASON FOR THIS PROGRAM The Electronic Shift On the Fly (ESOF) 4x4 system may shift from 4x2 into 4x4 without any input from the driver or it may simply become inoperable. This condition may be the result of GEM (Generic Electronic Module) system software concerns. SERVICE ACTION Owners are being notified to return their vehicles to their dealers for a GEM replacement which controls the 4x4 system. REFUNDS Only for owner-paid repairs made before the date of the Owner Letter (or after the date of the Owner Letter if an emergency repair was made away from the servicing dealer). QUESTIONS? Claims Information 1-800-423-8851 Other Recall Questions 1-800-325-5621
ATTACHMENT I Owner Notification Program 98B29 - B Program OASIS You must use OASIS to determine if a vehicle is eligible for this program. PLEASE NOTE Correct all vehicles in stock before delivery. PROMPTLY CORRECT -- Affected vehicles on the enclosed list. -- Other eligible vehicles which are brought to your dealership. DEALER-OWNER CONTACT Immediately contact any affected owner whose name is not on the list. Give owner a copy of the Owner Letter. Arrange with the owner for a service date. CLAIMS Enter claims using DWE. See ACESII Manual, Sections 5 & 6. OWNER REFUNDS See ACESII Manual, Section 3-59 for submission procedures. For owner-paid repairs made before date of the Owner Letter (or after the date of the Owner Letter if an emergency repair was made away from the servicing dealer), enter using DWE: Program Code - 98B29 Misc. Expense - REFUND Misc. Expense - ADMIN. Misc. Expense - 0.2 Hr. ATTACHMENT II Owner Notification Program 98B29 - B Program OWNER NOTIFICATION PROGRAM 98B29 Certain 1999 Model Year F-Series Super Duty 4x4 Trucks GEM Module Replacement PARTS REQUIREMENTS Parts will not be direct shipped for this program. Order your parts requirements through normal order processing channels. PART NUMBER: F81Z-14B205-DC KIT CODE: AA DESCRIPTION: GEM Module For vehicles WITHOUT Control Entry (RKE) PART NUMBER: F81Z-14B205-EC KIT CODE: BB GEM Module For vehicles WITH Remote Control Entry (RKE) SPECIAL INSTRUCTIONS Destroy and scrap old module. DEALER PRICE For latest prices, check or call your: Order Processing Center DOES II Updated Price Book EXCESS STOCK RETURN Excess stock returned for credit must have been purchased from Ford Customer Service Division in accordance with Policy Procedure Bulletin 4000. CLAIMS PREPARATION - Enter using DWE. - Use code information shown below: Program Code - 98B29 Labor Operation - See Above See Sections 5 & 6 of the ACESII manual for detailed instructions. Customer Notification Letter: January, 1999 Serial Number: 12345678901234567 98B29 Mr. John Sample 123 Main Street Anywhere, USA 12345 Ford Motor Company is providing a no-charge Service Program, Number 98B29, to owners of certain 1999 Model Year F-250/350 4x4 Super Duty series Trucks. REASON FOR THIS PROGRAM The Electronic Shift On the Fly (ESOF) 4x4 system may become inoperable. In some cases it may also shift from 4x2 into 4x4 with no input from the driver. This condition may be the result of GEM (Generic Electronic Module) system software concerns. NO CHARGE SERVICE At no charge to you, your dealer will install a new GEM module to correct these concerns. Your truck is eligible for this program through July 31, 1999, regardless of mileage. HOW LONG WILL IT TAKE? The time needed for this service is less than one half day. However, due to service scheduling times, your dealer may need your truck for one full working day. Please call your dealer for a service date. CALL YOUR DEALER Ask for a service date and if parts are in stock for Program Number 98B29. If your dealer does not have the parts in stock, they can be ordered before scheduling your service date. Parts would be expected to arrive within a week. When you bring your truck in, show the dealer this letter. If you misplace this letter, your dealer will still do the work, free of charge. REFUNDS If you paid to have this service done before the date of this letter, Ford is offering a full refund. For the refund, please give your paid original receipt to your Ford dealer. To avoid delays, do not send receipts to Ford Motor Company. CHANGED ADDRESS OR SOLD THE TRUCK? Please fill out the enclosed prepaid postcard and mail it to us if you have changed your address or sold the truck. We are taking this action as part of our ongoing efforts to maintain owner confidence in our products. We hope this program will confirm your continued satisfaction in your Ford-built vehicle. OWNER NOTIFICATION PROGRAM 98B29

3546 Santa Rosa Avenue, Bldg. F
Santa Rosa, California 95407

Email <mailto:[email protected]>

Product Name: Generic Electronics Module (GEM) with Remote
Keyless Entry (RKE)

Description: The GEM with RKE is a product which consolidates many vehicle electrical and electronic features in one package. It provides the customer convenience of remote entry via a key fob transmitter, or a door mounted numeric keypad to lock or unlock the vehicle. Additionally the GEM controls the 4-Wheel Drive Electronic Shift-on-the-Fly for vehicles with 4X4 capabilities. The GEM functions may be grouped into 3 areas: Remote Entry, 4X4, and Interior functions

:::Remote Entry::::: Unlock Driverís Door - Command Interior Lamps on and off Unlock Passenger Doors - Horn verify on lock
Lock All Doors - Allow up to 4 transmitters to be programmed for use Panic Alarm

::::4X4:::: Electronically shift the transmission from 2 Hi to 4 Hi while in motion Electronically shift from 4 Hi to 4 Low while in Neutral Detect and report faults via Instrument Cluster Telltale

:::Interior Functions:::: One-Touch Down Driverís window control - Headlamp On reminder Control of Battery Saver and Accessory Delay functions - Speed Dependent Interval wipers/washer - Front Door Ajar Warning Indication (Audible and visual) - Interval Wipers/Washer - Rear Air Bag Tone Request Applications - Safety Belt Warning Indication (Audible and visual) Key in ignition reminder - Brake Warning Lamp Control

Operating Characteristics:
Storage Temperature -40 to +105 C
Operating Temperature -40 to +85 C
Operating Voltage 9 to 16 V
Dark Current 5.0mA nominal
Operating Frequency 315.0 MHz

Height 44.50 mm
Width 88.92 mm
Length 191.83 mm
Weight 259 grams
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Old 01-30-2002, 10:54 PM
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Introducing Ford's GEM Module and How to Tackle Its Problems
by Lance Wiggins

With today's trucks getting more sophisticated everyday, technicians must be ready and willing to suit up for the big game against electronics. In 1994 Ford introduced the Generic Electronic Module (GEM). It was an innovative piece of technology, using multiplex communication for a variety of components, including wiper high/low switches, dome lamps, door ajar, and safety belts. In 1997 Ford began using the GEM module in their trucks for transfer case control with the 13-56, 13-54, 44-05 and 44-06 ESOF (Electronic Shift On the Fly) transfer cases, as well as the AWD systems. Problems with the GEM module in these trucks can cause the transfer case to get stuck in a single range. In this article of Let's Play Ball we'll tackle the fundamentals, operations and diagnostics of Ford's 4x4 systems and the GEM module. So let's suit up and Play Ball.
In 1997, all Ford F series, F350-F450, Ranger and Explorer went to the GEM module to help with the electronic 4x4 systems. These transfer cases are, as usual, backing up the trans. It is important to understand how the module works before you jump offside and receive a penalty, such as the customer saying, "It's doing the same thing," or the classic "It never did that before." Ford's ESOF (Electronic Shift on the Fly) system relies heavily on the GEM for proper operation. Now that we're on the field let's take a look at this system. The Electronic Shift on the Fly (ESOF) system is an electronic shift 4x4 system that allows the driver to choose between two different 4x4 modes, as well as 2-wheel drive. The driver can switch between 2WD and 4H mode at speeds up to 55 mph (88 km/h). To engage or disengage 4L range, the vehicle speed has to be below 3 mph (5 km/h), the brake pedal applied, and the transmission in neutral. The transfer case is equipped with an electromagnetic clutch inside the case. This clutch is used to spin up the front driveline when shifting from 2WD to 4High (4H) mode at road speeds. When you turn on the control switch the instrument panel to the 4H mode, the GEM recognizes that a shift has been requested. It then activates the electromagnetic clutch, and the relays that power the transfer case shift motor.
When the shift motor reaches the desired position (as determined by the contact plate position signal), the GEM removes power from the shift relays and motors. When the transfer case front and rear output shafts are synchronized, the spring-loaded lockup collar mechanically engages the mainshaft hub to the drive sprocket. Finally, the front axle collar engages, and the GEM deactivates the electromagnetic clutch.
Now that we've tackled the fundamentals of the GEM in relation to transfer case function, it's time to huddle up and talk about the electrical inputs and outputs the GEM needs to execute a change between 2WD and 4H. Feature inputs include:
4WD mode switch (various resistances; figure 1 and 1a
Contact plate position inputs A, B, C, and D (grounded when closed, open circuit when open; Speed sensor reading no higher then 55 mph (88 km/h) These are the only inputs needed to shift the transfer case from 2WD to 4H on the fly. Let's keep the ball on the ground and run to the output side of the system; feature outputs include: 4x4 shift motor relay outputs Transfer case clutch relay (grounded when relay is energized, open circuit when relay is de-energized) 4x2/4x4 vacuum solenoid (grounded when energized, open circuit when de-energized) Cluster indicators (grounded when energized, open circuit when de-energized) When these outputs are in place, the GEM can accurately determine what the customer's needs are and confirms engagement of 4H. Time to pass the ball down field and get that transfer case into 4L; feature inputs include: 4WD mode switch (Contact plate position inputs A, B, C, and D Output speed shaft (OSS) sensor (reference 0.7 * 20 volts, 2.2 Hz/mph). Transmission range sensor (grounded in neutral, open circuit in all other ranges). Start/clutch depressed input Now that we've covered fundamentals and operations of the GEM and the transfer cases, it's time to play defense against a GEM of a problem. When your customer comes in with the complaint "No 4x4 Operation," check to see if the 4x4 lights are flashing. If they are, it indicates a diagnostic trouble code in the system. At this point you'll need to access the GEM via the OBD-II diagnostic connector -- the same one used for all other system diagnoses. Using your scan tool, enter vehicle identification.
If your scan tool offers (GEM) trigger, select RETRIEVE CONTINUOUS MEMORY CODES. Most of the codes will be body codes (for example, B1852 or B1548). Remember to document any codes you receive -- you're going to need them later.
Now it's time to perform the Key On, Engine Off (KOEO) test. Prior to running this test, it will be necessary to close the power windows (if equipped) and turn off all accessories (this will prevent false codes). Trigger the KOEO test: You'll notice some different routines you're probably not used to seeing. For example, the windshield washers will spray (a great way to get back at your buddy if he happens to be standing by the door during your test), the 4x4 lights will self test, windshield wipers will oscillate, and the dome lamp will go on and off. These self-test functions are not the same for all models and years. Some will only cycle relays in the dash. These are all normal operations of the KOEO test (remember to document any codes).
In some cases it will be necessary to locate pinpoint tests for the codes you receive (if you receive a pinpoint test, don't skip over it; it could lead to misdiagnosis). Yeah, it's 4th quarter, time to send in the best defense you have against this GEM of a problem. There are two very common problems with the GEM controlled systems: No 4x4 Engagement and Stuck in 4x4 Low. Here are some quick diagnostic tips to help you locate the system at fault.
Let's start with No 4x4 Engagement. Remember, there are only three inputs needed to operate 4High: mode switch, contact plates, and output speed sensor. Before you test drive the vehicle that won't engage in 4High, start the engine and watch the 4x4 lights self test (blink on and off). If the 4x4 lights blink, it proves the GEM is capable of receiving input signals. Next, see if you're getting a good vehicle speed reading during your test drive. A speedometer reading proves you have a good VSS signal to the cluster. This leaves you with only three items to look at with your scan tool: vss signal at the gem; contact plates A, B, C and D; and the mode switch . You have successfully cut the system in half. Your diagnosis will be a lot easier with only three signals to look at. If the input signals are within specifications, look for a problem in the GEM. Always check your power and ground supplies before replacing the GEM Now let's look at the second common problem: Stuck in 4x4 Low. This one is a little more involved to diagnose. First verify the problem: Usually the complaint will be "I came out of my house, jumped in my truck, put it in reverse and it was in 4x4 low." In the mean time you're looking at your service manager or partner, saying "this person doesn't know how to put his truck into 4x4 mode; I bet he's never even used it." And sure enough, you hop in the truck and it's working fine in 2WD. Quick questions for the customer "Did you try your power windows?" or "Did your dome light come on?" The answers to these questions will give you an idea as to whether the GEM module was working. If the dome light and windows do not work it's a good sign that the GEM is faulty. If the problem is intermittent have your customer check the dome light and windows when the problem occurs. Again, check for codes. There are only three inputs you need to look at: VSS at the GEM; contact plates A, B, C and D; and the mode switch. Stay with the game plan and you're bound to win. Today's transfer case diagnostics aren't going to get any easier; the GEM modules aren't going to go away. So before you throw an interception, keep your game plan simple, get to the point and tackle the problem head on. And That's the game!
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Old 01-30-2002, 10:55 PM
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Another GEM of a Problem
by Lance Wiggins

Here we go again, another GEM (Generic Electronic Module) controlled 4x4 problem in a Ford F-150. It seems like just when you get a grip on the system it hits you from behind. Almost like this new football league where the cheerleaders are the center of attention. You can find yourself watching the wrong game and just when you think you're focused and aware of what's going on, it's commercial time. In the transmission game it's very similar. In this issue of Let's Play Ball we will cover Another GEM of a Problem. The HelpLine is a great source of information, it gives us an opportunity to hear a concern, find the problem, and repair it. But, we can't do it alone; we need you to be our hands, eyes, and ears. This is where Jeff Rauch came to play. Jeff is from Certified Transmission in Olathe, KS and did he ever have a GEM of a problem. The concern was the 4X4 light was always on. I received a message from one of the technicians and was told Jeff had performed all the diagnostics in the trouble tree and had come up short of the goal line. Shortly after I made the call, Jeff answered the phone, "Hi Jeff, Lance here from ATRA. I hear you have some questions about the GEM." Jeff was very knowledgeable and mentioned he was a little frustrated with this unit. Jeff said, "I have been through all of the diagnostic tests and concluded the relay was bad. I replaced the relay and it worked for half of the test drive and went back to the same problem." I asked him if there were any trouble codes in the system, he mentioned there was a code P1828, so we decided to attack that code head on. But before we go to P1828, let's perform the necessary pretesting. As with any diagnosis we do, there will always be pretesting before you go to the specific code diagnostics. Easy tests like: checking for adequate battery voltage (>12.5) at the fuse; does the ignition register on your scanner? Scanners play an important part in diagnosing, by allowing you to look at important inputs and outputs. With Jeff on the other end of the phone the playing field was set and we were going to battle. Diagnostic Trouble Code P1828 refers to transfer case shift relay circuit concern. The first operation of this trouble chart is to activate the relay. This operation lets you know whether the GEM is capable of receiving a signal from the scanner and if the GEM is capable of sending the signal to the relay. This test will also reveal whether or not the wire is capable of transmitting this signal. Unfortunately, Jeff quickly let me know his scanner was unable to perform this test. Well that's just short of a pass interference penalty. Well ok, I can see we're going to have to play the running game here. We moved to the circuit checks from the GEM to the transfer case it, was the only other choice we had. I explained to Jeff that this was probably not going to be easy, he jested and replied "it's already a pain in my butt, I just want it fixed." The hardest part about checking the GEM is the location. The GEM is located behind the fuse block; it rides "piggy-back" on the fuse block (Figure 1). The connectors from the fuse block to the GEM are molded on the fuse block and GEM (Figure 2A,2B). I told Jeff, "Accessing the GEM for testing is no easy first time operation." Jeff said, "It's more like contorting yourself in to a brake pedal to remove the two connectors on the back of the GEM." I agreed and comforted him with the old "it will be easier next time." Once we had the GEM accessed it was time to test. I faxed Jeff the testing procedures out of the Ford shop manual, now the game was in his hands. A short while later I received a message to call Jeff at the shop, I was very excited to find the outcome. Unfortunately, Jeff was in the same field position he was in when we hung up the phone, third down and a long 25 yards to go for a first down. Jeff sounded discouraged, the tests that I sent him he already had. He explained the testing came up with the same result "replace the relay" (Figure 3). OK, so we performed all the recommended testing and came up with the same result, I thought we might have missed something so I said, "Let's go through the test together." One thing to remember when following diagnostic procedures, the top of the test always tells you what component or circuit you're testing. When we started the diagnostic routine it was obvious Jeff had performed the testing correctly, however there was one test that sent us in the wrong direction. It was the last test of the trouble tree; in the previous tests we checked the battery voltage from the fuse panel to the transfer case. We checked the wiring from the GEM to the transfer case. We checked the relays for operation by turning the key to the run position. By the time we arrived at the final test and I do mean final test, you know the test that only gives you the replacement of a component or the repair of the wiring harness. Most of us don't like the final outcome, especially when it refers to a component replacement. All of us have been there, you replace the computer or sensor and low and behold, let's say it together, "IT STILL DOESN'T WORK." So there we were, faced with the question, is resistance between 60 and 160 ohms? Jeff answered "no," so replacement of the relay is the answer, but low and behold, "IT STILL DOESN'T WORK." Jeff, I recalled had this, I want to laugh but I'm mad tone to his voice. I stared at the trouble tree for a few minutes and said, "Jeff your going to be happy when you fix this vehicle, it may take a while, but we'll fix it." I went back a few steps and I think we both asked the same question, "Was the relay supposed to be plugged in during this last test?" As I recalled the testing we had just gone through, at no time did the test say to reconnect the relay. "Wait a minute," I said, "Let's look at the top of the test (Figure 4). What does it want us to test? It wants us to test the transfer case shift relay coils."So with the relays installed to the fuse block and the GEM connected, testing the shift relay coils from the transfer case connector threw the GEM to the relays, the question is, is the resistance between 60 and 160 ohms? With this question at hand, Jeff went on to the test. A short while later I called Jeff, "What's the verdict?" Jeff said, "With the GEM plugged in and the relay plugged into the fuse block, the resistance was 85 ohms." Now the test result is a little different. The result is the replacement of the GEM. Jeff was not enthusiastic about that. I explained to him that I ran into this problem many times, more often then not, the fuse block is the cause. Because the fuse block and GEM are riding "piggy-back," the connection is pretty good. The problem I found is water intrusion or internal wiring problem in the fuse block, the GEM happens to be the fall guy. Since the relay for the GEM was tested correctly, it could only be the GEM or the fuse block. Jeff was still a little skittish and I could understand, but the bottom line is we need a first down and if we had to go deep, we don't have much of a choice. The test was incomplete and it took both Jeff and I to look deeper in to the system. This is the best way to describe "Teamwork." I think it was a day or so later when I received a fax from Jeff. The fax, I have to admit, brought a big smile to my face. The fax read, "One Ford F-150 4X4 with fully functional 4-wheel drive ready to deliver, GEM and fuse block did the trick. Thank you very much for your help, Jeff." I have installed the R&R of the GEM for you, this may help in the future.
If we stop to smell the grass before the game, will you get a better sense of the opponent? In this case the GEM and fuse block was the undefeated team, and we won. Until next time, keep it simple and play hard. And that's the game...
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Old 01-30-2002, 11:01 PM
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GEARS Magazine
-- November 2000


... In this article of Let's Play Ball we'll tackle the fundamentals, operations and diagnostics of Ford's 4x4 systems and the GEM module. So let's suit up and ...

GEARS Magazine -
May 2001


... GEM of a Problem by Lance Wiggins. Here we go again, another GEM (Generic ElectronicModule) controlled 4x4 problem in a Ford F-150. It seems like just when you ...


... Ford Recalls Certain 1999 Model Year F-250/350 Super Duty Series 4x4 Trucks- GEM Module Replacement Provided courtesy of Gabe Deno aka gdenoPSD -. ...
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Old 01-30-2002, 11:02 PM
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Electronic Shift on the Fly Recall (ESOF)
Component: ???
Mfg. Campaign #: 98B29
Year: 1999
Model: ???
Manufactured From: FEB 1998 To: AUG 1998
Year of Recall: '98
Type of Report: Vehicle
No Official Information Found Yet.
1999 Super Duty trucks with electronic shift-on-the-fly 4WD have a problem with 4X4 not engaging properly or engaging when it shouldn't. There are both temporary and permanent fixes for the problem.
The temporary fix is to reset the computer by either disconnecting the batteries or by pulling fuse #15 from the fuse panel. Leave disconnected for 10-15 minutes. After hooking the batteries back up or replacing the fuse, your 4X4 should start working again. Only do this in an emergency as it resets all the trouble codes. If you are stuck though, you have no option but to do this.
The permanent fix is to have the dealer install the new updated GEM module. This will permanently fix the problem. All trucks built since around August 1998 should have the updated module installed at the factory.
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Old 01-30-2002, 11:04 PM
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A: This is an unpleasant example of what can happen to a modern vehicle when electrical or mechanical parts become damaged during a theft attempt or collision. One would assume the visible damage to the vehicle or having a stranger violate your personal space is bad enough, but now this.
It sounds like there was some damage done in the driver's side door, possibly to a section of wiring or to one of several switches. Also, a good number of body features (interior lamps, warning chimes, door locks, power windows, vehicle alarm, to name a few) are controlled by the GEM (Generic Electronic Module). This box, located in the instrument panel just behind the radio, replaces a dozen or more individual controllers, simplifying the Explorer's electrical system. It's possible the module or some of the wires connecting to it were damaged during the hasty removal of the radio.
What should you do next? If the electrical faults happened as a result of the theft, their repair should be part of the insurance claim. I'd contact your insurance company, and ask that the diagnosis/repair of the electrical faults be subcontracted to a Ford dealer. Why the dealer? Their diagnostic techs can communicate with the GEM module, using an NGS (New Generation Star) scan tool, retrieving fault codes and performing the necessary diagnostic procedures.
This level of diagnosis/repair will be over the head of the body shop and the majority of independent shops, unless they possess an exceptionally competent after-market scan tool, factory-level diagnostic charts/diagrams and have experience with multiplex body control systems.
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Old 01-30-2002, 11:05 PM
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Ford Body Systems Software Cartridge
Vetronix ScanTest software for Ford vehicles provides many data parameters, trouble codes read/clear functions and Bi-Directional output controls. The diagnostic power included in the Ford Powertrain </diagnostics/scantest/ford_powertrain.html>, Ford Chassis </diagnostics/scantest/ford_chassis.html> and Ford Body cartridges cannot be matched by any other tool.
The Ford Body Systems Software Cartridge is used with the Tech 1/1A, or Mastertech diagnostic tester to efficiently diagnose Generic Electronic Module (GEM) Electronic Control Assemblies (ECAs) used in Ford, Mercury and Lincoln vehicles.
GEM diagnostic support for:
1995-2001 Explorer, Ranger and Mountaineer
1995-2001 Windstar
1996-2001 Taurus and Sable
1997-2001 Expedition and Navigator
1997-2001 F150 and F250 Trucks
1999-2001 Mustang
1999-2001 F-Series Super Duty Trucks (F250, F350, F450 and F550)
2000-2001 Lincoln LS
2001 Explorer Sport Trac
2001 Escape
Supports new Snapshot triggering functions with Continuous DTCs.
System Diagnostics
Read & Clear Diagnostic Trouble Codes (DTCs) - This feature allows the user to read Continuous, On-Demand, Front-Wiper On-Demand and Rear Wiper On-Demand trouble codes including DTC number, DTC description, and DTC pin point test displayed on the screen.
Data List - This feature allows the user the insight to serial data from the Generic Electronic Module's input and output circuits. These parameters are great for component and circuit diagnosis.
Snapshot - This feature allows the user to capture data list values over a period of time and stores them into memory. The snapshot can be triggered manually by the user or by the DTC. The snapshot can then be replayed for troubleshooting intermittent problems.
© 2002 Vetronix Corporation. Home Page
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Old 01-31-2002, 02:18 AM
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TSB Article #98-23-1, "Water Intrusion Into The GEM Module-Service Tip"

The GEM is located behind the dash fuse box on our F-150's. There have been a number of areas that allow water to leak into the cab.

The problem with the GEM is that water leaks in through the windshield, cowl, or door molding and the GEM is mounting is such a way that water gets in and has no place to go resulting in corroded contacts.

It controls:
- Wipers/washers.
- Warning chimes.
- Battery saver.
- Illuminated entry and courtesy lamps,
- Driver power window.
- Accessory delay.
- 4-Wheel drive.

The new GEM has a plastic watershield.

My suggestion is to contact a dealer service dept with the above TSB # and see what the cost of service and replacement is.

If you are up for the challenge then you are certainly free to tackle this yourself as well but personally don't have any suggestions on how.

***It's not that I don't have sympathy for the problems you're having. It's just that I've spend many hours fixing Ford's developmental problems and accepted thier tendancy to forgo R & D in favor of TSB's***

Please don't copy and paste several lenghty articles. It's not properly formated and gets terribly annoying

Last edited by AjRagno; 02-01-2002 at 12:47 AM.
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Old 04-12-2011, 04:13 PM
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1997 stuck in 4lo

1997 4.6 vin w esof ....motor new,switch new still stuck in 4lo is gem causing to stay
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Old 04-13-2011, 12:33 PM
glc is online now
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Why did you tack this on to a thread that died 9 years ago?
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Rebel Off Road
2009 - 2014 F-150
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