I have a 2003 F150 with the 4.6 V8. My truck holds 25 gallons of fuel and my low fuel light isn't working. Does anyone have a good idea of why this might be the case.

Thanks,

Brian

 

How are you testing that it is not working ?

When you turn the key to the on position ( without starting it ) does the low fuel light on the cluster come on ?

The reason I ask, is all I can find is the fuel pump assembly that has the fuel pump module and fuel tank pressure sensor in it.

Both of these feed the PCM as well as the instrument cluster.
The cluster uses the fuel pump module to change the level on the fuel gauge, and once it reaches a low enough resistance, triggers the low fuel light.
The resistance changes between 22.5 ohms ( low ) to 145 ohms ( full ) on the float.

If the fuel gauge does not drop below a certain point, then the float might be stuck, but this would show up as no low fuel light, and the gauge does not drop beyond a certain point.

Try using the DTM mode on the odometer and see what the PCM reads the fuel level as, when it is almost empty

( DTM in next post )

 

Activating Test Mode

To enter the HEC Dealer test mode, depress and hold the instrument cluster SELECT/RESET button, turn the ignition switch to the RUN position, and then continue pressing the SELECT/RESET button (5 seconds) until tESt is displayed in the odometer. The SELECT/RESET button must be released within 3 seconds of the odometer tESt display to begin the dealer test mode.

Depress the SELECT/RESET button to advance through the following steps until dtc is displayed. Depressing the SELECT/RESET button will display any stored continuous DTCs before proceeding to the next step.

GAGE
Activates gauge sweep of all gauges, then displays present gauge values. Also carries out the checksum tests on ROM and EE. If the gauge sweep is inoperative, INSTALL a new instrument cluster.

All segments illuminated
lluminates all odometer segments. If any odometer segment is inoperative INSTALL a new instrument cluster.

bulb
lluminates all micro-controlled indicators and LEDs. Install a new indicator or LED as necessary.

r
eturns to normal operation of all micro-controlled indicators and LEDs and displays hexadecimal value for ROM level. (used when requesting assistance from the hotline). If alternating flashes for FAIL and ROM level are displayed, INSTALL a new instrument cluster.

EE
Displays the hexadecimal value for EE level (used when requesting assistance from hotline). If alternating flashes of FAIL and EE level are displayed replace instrument cluster.

dt
Displays hexadecimal coding of final manufacturing test date (used when requesting assistance from hotline).

dtc
Displays continuous DTC's in hexadecimal format. Pressing the SELECT/RESET button will display any DTCs stored before proceeding to the next step.

enG
Displays the English speed in MPH. Speedometer will indicate present speed within tolerances. Display will show 0 if input in not received. If input is invalid for one second or more, or if speed is 0.

m
Displays the metric speed data in kph. Speedometer will indicate present speed within tolerances. Display will show 0 if input in not received. If input is invalid for one second or more, or if speed is 0.

tAc
Displays the tachometer data received from the PCM via the SCP network within tolerances. Tachometer will indicate present RPM. Display will show 0 if input is no received, if input received is invalid for one second or more, or if engine RPM is 0.

FUEL
Displays the code (0-255) for the fuel sender input to the HEC. The fuel gauge will display a filtered fuel level value. This filter will keep the pointer from moving suddenly or erratically.
255 open send +/- 0
232 full stop +/- 0
215 Full mark +/- 10
178 3/4 mark +/- 8
138 1/2 mark +/- 7
93 1/4 mark +/- 5
41 E mark +/- 4
54 Low Fuel (0-59)
0-18 short (0-20 max)

OIL
Displays the code (0-250) for the oil pressure switch input to the HEC. Oil pressure gauge will indicate present oil pressure. Normal oil pressure (greater than 6psi) will display a value between 000 and 176. A low oil pressure or an inoperative engine oil pressure switch (less than 6 psi) will display a value greater than 176.

dEGC
Display of engine temperature in Degrees C input from cylinder head temperature sensor.
49 C "C" mark
60 C Normal band start
120 C Normal band end
-40 C No SCP message for 5 seconds

bAtt
Displays the code (0-255) for the battery voltage input to the HEC. Battery voltage gauge will indicate present battery voltage.
93-102 6.2-9.1 volts, low voltage
115-124 8.5-10.7 volts, Normal band start
215-225 15.8-18 volts, Norm band end
230-241 16.9-19.1 volts, high voltage

rhEo
Displays the present decimal rheostat dimming input, 0-255 (used when requesting assistance from the hotline)

rhi
not used

rhS
not used

rho
not used

Cr
Displays the current RUN/START sense input. Display will show -h for high input with the ignition switch in the START position and -L for low input with the ignition switch in the RUN position.

PA-PE7
not used

GAGE
Repeats the display cycle

 

Where is the the following part that you stated? You said to depress and hold the instrument cluster SELECT/RESET button. The fuel light does not come on when the key is on the on position before I start it. I have noticed that it takes about 7 seconds for my instrument cluster gauges to start working. I think we are on to something here?

bixbystx

 

Sorry this does not make any sense.

The fuel light does not come on when you turn the truck to the on position ?

Did you run the DTM, and did the bulb light when it got to the bulb test ?

When you say it takes about 7 seconds for the gauges to start working, is this all of them ?

 

No the light didn't come on when I did the bulb test, which kind of scares me a bit. I also got the following DTC's.

9356 Ignition Run Circuit Open
5284 Oil Pressure Switch Failure
D262 Missing SCP Message

Yes it takes about 7 seconds for my gauges to start working when I turn the key on. This doesn't sound good but it might not be a huge deal.

Thanks,

Brian

 

And yes it is all of my gauges!

Brian

 

pull the cluster and replace the bulb, actually replace all of them.

When you put the cluster back in, you can see if the gauges work better.

Oil pressure, yep. The truck was not running right ?

 

Correct, the truck was not running. It really doesn't look like it will be that big of a chore to pull the cluster. I will change all the bulbs and see what happens. I might need a new cluster and I have seen those online for about $90 with a warranty. I just don't know why it takes so long for my gauges to start working. I guess that is electronics and PCM stuff. I will let you know how it goes. Thanks for your help SSCULLY.

Brian

 

In the How to forum, there is a thread on changing the color of the lights, that has directions on pulling the cluster out.

https://www.f150online.com/forums/ar...r-97-03-a.html

If you need to replace the cluster, it might work swapping the HEC from the back of the cluster and putting a new one in, if it comes to that.

The HEC if where the PATS info is stored, so without it, you will get a crank no start, and the theft light will be going mad.
I'll start taking a look for a thread on the HEC swap ( hope I can still find it ).

EDIT:

Found the threads by Jeff, and the electronics that control the gauges is in the HEC, along with the PATS info ( found from the non-tach to tach swaps in 99-03 MYs ).
So if the electronics of the cluster are causing the problem with the gauges, then it would be a dealer trip to get the new cluster installed and working.
This would be a HEC erase, and reprogram the keys as new keys, and set the PCM ID in the HEC ( actually erase the PCM ID and use a programmed key to get the HEC to read the PCM ID ).

Let's hope we do not get to that point. When you have the cluster out, check for cold solder joins on the back.

Those 2 additional codes are a bit interesting( keep mulling around how those might come up without being a problem, not having much luck ) , the oil one is a given.

 

I really do appreciate all the info that you have given me. You are a good man. I hope it doesn't get too nasty. My gauges still work and all the lights expect my low fuel. My truck runs fine which is a plus so I guess I could be in a lot worse shape. That 7 second delay just gets on my nerves and I'm one that has to have everything perfect or I obsess for some reason. I was looking at some of the instrument clusters at egauges.com and the have some sweet aftermarket clusters but I'm not going to pay $300 for one of those when I can buy one that will carry a warranty for around a $100.

Thanks,

Brian

 

I have tried everything and I think I'm going to get a new instrument cluster. I took my old one apart and all the bulbs were fine. I think I will get a cluster off of ebay for a reasonable price. No way I'm going to Ford to buy one. I know Ford needs all the cash they can get but there is no telling what they would charge for that. If I do get a new instrument cluster, will it have the motherboard with it. Does it all come as one piece? That is probably a silly question but I thought I would ask before I order.

Thanks,

Brian

 

The brains of the cluster, and the PATS info in on the board on the back.

If the gauge is broken ( not the electronics for it ) then swapping your board to the "new" one would do the trick, and the PATS info and millage transfers with it.

If the electronics for the gauge is the problem, then this swap won't work. If you put the new one in without swapping the back board, your truck will not start. Wrong PCM ID in the HEC, and the PATS keys will be wrong.

 

So do you think it definitely sounds like I have a problem with my instrument cluster? I changed all the bulbs and have the same problem. I don't plan on buying a new cluster from the dealership because they are too darn expensive. I figure I can probably get one from a wrecked truck that will work on my truck. Do you think this is possible? I also found a guy in town that works on cars and the electronic or ignition part of a car is his speciality. Do you think it might be worth my time to go and get an opinion from him? If I buy a cluster, will it include the back part of it also, the brain part? I assume it would be I just wanted to make sure.

Thanks,

Brian

 

I got a new instrument cluster from a friend that had a 2003 F150 just like mine. How much could I expect Ford to put my instrument cluster back in and reprogram it for the new cluster. I would like to put the cluster back in myself but I know Ford won't play that game. It is such easy work to put a new cluster back in but I know how these dealerships operate.

Brian