Here we go. I have a 2005 F150, XLT supercab, power windows, locks, auto, 4X4, 5.4. My issue is this. Sometimes my gauges (fuel, tach, speedo, amp, temp, oil pressure as well as the odo) stop working, and when this happens the Power point stops working, as well as the door sensors, and the HVAC system turns to defrost and hot. The first time this happened it started working again on its own in under 10 minutes. After that some how I found that if I slammed the driver door they would start working again. Then One morning I found if I push the Trip/odometer button it would come back on. I then noticed that sometimes when they come back on the Odo reads "Zone 8", and sometimes it says "Sweep Gauges" When It says that, you can keep pressing the button and toggle through the oil pressure, tach, fuel pressure, so on and so forth. At that point I need to turn my truck off, and restart it to get it to go away. I have been told by a mechanic at my work that it may be the GEM. My question is this. Does it sound like a GEM issue? And, what GEM is it, and where is it located, so I can get this issue taken care of? Thanks ahead of time!

 

2005 does not have a GEM ( that is a 97-03 item ), the "mechanic" at your work, don't take advice from.

From the symptoms, sounds like you have a battery that is dying.

 

All that caused by a dying battery? Strange, I guess I'll get it tested.

 

Microprocessor-controlled equipment can be finicky if it doesn't have stable and reliable operating power.

 

That doesn't make any kind of sense to me at all. The truck is running when this happens. Not off. So, for this to be a battery issue, it would also have to be a cause of a bad alternator right? Maybe there is something I am over looking. But How could a bad battery effect a running truck? The volt meter never drops, and I have no dimming of lights at night when running the radio, ac, and whatever else. If someone could explain how this is a battery issue I would be very happy.

Also, the Mechanics that I work with can't see how this would be a battery issue. And they can be trusted, they have about 60 years combined experience.

 

A bad battery does not mean a bad alternator.
You can have a cell in the battery that is sulfating or shorting, causing a loss of a fraction of the total voltage. Batteries do not last for ever, and some of the cheaper ones ( Battery Plus junk ones ) only work flawlessly for ~ 12 months.
Could also be a bad ground, but this is why you start the diagnoses with having the battery tested. If you would rather, go find every ground from the battery to frame to truck, remove and clean them, and check every crimp. It is a lot of work, that might not be the cure, this is why to start with some easy, load testing the battery.

They can be trusted ? They are the ones that told you it was the GEM, something that does not exist on a 2005.
They might have 60 years combined experience, but they don't know squat about a 2005 F-150.

If you want to trust them, go for it. Good luck finding the GEM in your 2005, you are going to need luck to find it.

 

Wow, Thanks for being a huge help. There is no need to get all hot, and treat people like they are idiots. For a first post, and asking for help, and explaining why I had my questions about your solution, you sure do treat me like you know everything. I'm sorry if you have more experience than my mechanic co-workers. You may be right in the fact that they may know nothing about a 2005 F150, but they do take care of 300 vehicles in our fleet, from International 7600 dump trucks, to Dixie Chopper lawn mowers. That is why I would trust them, over you, who I know nothing about, and who for all I know, know as little as you accuse my co-workers of. I'll have the battery tested. If it is the problem then thanks. If not, I guess I’ll start to test all those crimps and grounds! Please in the future, try at least to make this site feel accommodating to new posters, or the new ones will find another site to ask their questions on.

 

First, if you trust them so much, why come here asking in the first place? Secondly, Scully knows more about electrical in these vehicles than most of us combined. He is an expert. Next, he was very curteous with his reply, he was just pointing out some flaws in your thinking and you are the one who got rude. If you do not want advice, don't ask for it.

Lastly, if it were me, the first thing I would check is the battery. It has happened to many of us, including me. Left me stranded with no warning.

 

To answer your question. Do you ever take advice from people and never ask another question about it ever again? I could blindly trust people, but in the past that has not worked out for me. I would much rather ask 10 people, and get 4 of the same answers and go that route, than to ask one person, and get the wrong advice. Did I expect a different answer? I don't know. But thats how I troubleshoot. I could find no answers anywhere else online for this problem.

Second. I think It is rude to challenge someones trust. A person who works on cars for a living more than likely has some sort or knowledge. These are not just guys off the street who have replaced a radiator, or an intake. These are trained, certified Mechanics. How many changes have been made to the F150 in the past 10 years? My final point on the issue is this. Telling me that the "mechanic" that I asked should not be trusted. That isn't nice, and I believe its rude. All I asked is why.

In the vehicles that I have dealt with in my life, they will run with no battery, so how is it that a "dying" battery would cause this problem. I could understand a dead battery or an alternator would cause it. This problem has been going on for over a year, it rarely happens unless there has been rain, or heavy frost. I haven't had to get a jumpstart since this started happeneing. Anyway, Im going to get the battery tested.

I have seen in the past on other message boards, that members seem to stick together. thats awesome, but don't blindly think something because you are buddies, or he has been here longer than I have. I'm over it. I feel like he was over critical of a friend. If hes an expert he should realize that other people don't know as much as he does and cut them a brake. See my point? I doubt it but whatever!

 

I will say one more thing, then I will let it drop. I think you need to step back and reread Scully's post and then your post. He is not questioning your friends' character. All he said is if these guys told you to look for something on the truck that does not exist, isn't it possible that they don't know what to look for in solving the problem? These trucks are extremely complicated, especially the electronics. That is all I see him saying.

Also, as a Moderator here, I do not take sides. I may cut some slack at times, but I try to look at every post objectively. All I saw was you overreacting to something someone said while trying to give you some help.

I sincerely hope you find your problem. We welcome you to the site, and hope in the future, you will be helping others as well.

 

I guess you don't trust anyone here, so why ask for input ?
You feel it is rude for me to question your lawn equipment mechanics, but you are good with questioning 2 members that gave the same answer, by your own post you do not trust us. If you don't trust the info you got here, why ask ?

A trained, certified Mechanic does not have training on every mechanical thing on the planet. They might have certifications from the lawn equipment you have, but that does no good for a Ford.
Truth be told, I am not a mechanic.
I guess members should stop listening to me about Electronics on F-150s, as I do not have the certifications from a training class. You already don't trust me ( due to questioning my answer ), so good luck with your problem.

To answer your question, A LOT has changed on the F-150 in the past 10 years. When I say A LOT, I mean 70% + of the electronics. Not even going to the looks, frame, or features or PCM software functions.

Go from a 1995 to a 2005, and this is light years of change, including the GEM. The GEM was introduced in 1997, if my memory serves me correctly. 1996 and older, there were individual modules ( LCM for Lighting Control Module, WCP for Wiper Control Module are the 2 examples that I know changed from 1996 to 1997 ) for the functions controlled by the GEM in 1997 to 2003 MYs.

2004 - 2008 MYs, control functions were moved from the GEM to the individual items. The wiper speed control was moved from the GEM to the wiper motor. The OTD ( One Touch Down ) driver's side window was moved from the GEM controlling relays to the driver's side switch itself in solid state control.
Interior lighting control was moved from the GEM to the Instrument Cluster.

These are just the items I can think of without looking for external module to GEM to solid state control, I know I am missing another 100 + items. Cruise control was another big change from 2003 to 2004 ( electronic control of a mechanic cable to throttle by wire ).

When you move from the 2004-2008 series to the 2009 + MY F-150s, you change everything again. The Central Junction Box is now a Smart Junction box, that controls everything. The SJB operates the individual lights with FET protection, and the switch is now just signaling the SJB with what it should do ( turn on the headlamps, to make a turn signal work ). The MFS is no longer a load carrying switch for the rear turn signals and brake lamps as well as headlamp operation. The MFS now signals the SJB, and the SBJ makes the brake lamp turn on, or the headlamps go from low to high.

Starting to get an idea of how much has changed in 10 years on a F-150 ? The short answer is clean consistent power is a firm requirement with a F-150 from 1997+.


Sorry if you think it is rude for me to say stop taking advice from someone that knows nothing about a F-150.
Plain and simple, they are giving you bad advice, and the good advice to this is stop trusting them about your problem. Nope, you feel it best to call me names......nice that you went to that level.
If you want to listen to your mechanic friends, good luck with that.

Welcome to a car from this century, if any other car you had would run without a battery. A 1997 + MY F-150 will not run without good battery in it.

I was not critical of your friend the lawn equipment mechanic, I was correcting his knowledge of a F-150.
You are the one that took it as a person attack, not what was typed, questioning his abilities to work on a modern Ford product. Please do not read into what I type, read what was actually typed.

Good luck with you problem, due to your attitude and name calling, ignore list you go

 

HAHAHAHA, See, Im the bad guy right, trying to insult people he doesn't even know.
I'll be happy to tell the police and truck drivers that they drive lawn equipment. You are a real winner!

 

I just started having this EXACT same issue with my 06 F150 XLT Supercrew. From reading the previous comments, I went to Advanced Auto and had my battery checked and everything was fine. Have you had any luck diagnosing your problem?

I am no car expert and would appreciate any additional information that anyone could provide on what to try/do next.

Thanks,

 

Nope, No luck so far. I am a few months away from my wedding and in the middle of a house remodel, so money has been tight. Mine tested fine as well. I'll replace it in July after all the fun and games are over.

 

So here we are months from the original post. My Battery Finally died 2 days ago. I went a purchased a new one yesterday. Funny, on my way to work today the gauges stopped working again. Let me first say haha, SScully, I wasn't flawed in my thinking that the battery wasn't at fault, and you are wrong. Second, does anyone have any ideas that don't insult people they don't know to fix this issue? THe following things happen as well when this happens. THe Radio sometimes stops working, but only the radio. Other times the gauges stop, and when they do the AC also stops working, not the fan, just the compressor. If I push the ODO rest button, slam the driver door, kick the side of the pedal compatment (door side not center), or lightly rap on the dash they start working again, sometimes for days and sometimes for seconds. any help would be great.