All instruments quit working at once on my 97 F-150 - speed, tach, fuel, volts, temp, odo, trip odo, oil. All idiot lights have failed except battery and seat belt. Indication for Overdrive is not working.

I have checked all other equipment and can find nothing else that is not working. I have checked the 50 A fuses (20 and 21) under the hood and also the 5 A fuse (2) under the dashboard, all are ok. Fuse 18 is also good, and the dashbard illumination is working. All fuses checked visually and with a meter. The annoying chimes are all working. The hi-lo beam indication, auto down feature for the drivers side window, and all features associated with wipers are working.

Checked for OBDII codes, passed with no codes listed, although the idiot light is not working.

I have been searched this site fand read many posts. I think I saw a thread somewhere that stated that this was probably a GEM problem, any ideas?

I had started a thread in the electrical forum but response was light, thought I would try here, seems like there is more traffic here.

 

no power to dash when the key is in the on pos.? cuz same thing here!

 

1997 and 1998 F-150 models are notorious for GEM problems that stemmed from a leaking windshield that gets water into the GEM and sets up corrosion in it. Usually strange electrical problems crop up to plaque the vehicle. The GEM controls a lot of things by completing the ground path for relays and other low current circuits. It is possible that your trouble is GEM related. The GEM is located under the dash on the driver side of the truck. It is on the back of the fuse panel. Take it out and look for signs of water damage and corrosion. Good luck!

 

GEM cost about $300 can.

 

Take a look at this thread, it gives a rundown of what the GEM does.

https://www.ford-trucks.com/forums/185379-how-many-gem-systems.html#post1195869

 

I had the same problem with my '97 F-150. I replaced the GEM and that fixed everything (including the fuel gauge which had always been somewhat erratic). No reprogramming of the new GEM is required with the possible exception of reprogramming the remote door lock transmitters.

 

I have finally tired of wondering how fast I am going and how much fuel is left. I am going to tackle the GEM. Finally found the information below in an old thread. Looks like it will benefit many others to have some directions when replacing the GEM. I will let you now how it goes:

After rereading your post I should say that I dont think your radio problems are caused by your GEM. Chances are the problem is in the radio unit itself. The other problems could easily be the GEM or fuse box though.
The GEM is attached to the back of the fuse box or as the manual calls it the "instrument fuse junction panel". I guess "fuse box" was too easy
Look carefully above the fuse box for any signs of water that has dripped down....stains, clean lines in the dust etc.
I've never had any luck drying out fuse boxes but some people have.
As for what manuals are good.....some people here highly recommend Haynes manuals but I always use genuine Ford ones.
Apparently the Ford cds and dvds can be found easily on Ebay and sell for not too much money. The Ford cds usually cover only one year of either car or truck while the dvds covers many years of all lines.
Also take a look at motorhaven.autoanything.com and see if you can find a manual for your truck there.
A site with some online manuals that isnt too bad is

As for what the GEM controls here is what the manual says....

GEM Features and Functions
The GEM controls the following features:

Wipers/washers (front/rear).
Warning chimes.
Battery saver.
Illuminated entry and courtesy lamps.
Driver power window.
Accessory delay.
4- Wheel drive.


I cant post the pictures from the manual here but the instructions for replacing the GEM/fuse box are.........

--------------------------------------------------------------------------------

Generic Electronic Module (GEM)

Removal

Disconnect the battery ground cable (14301).

Remove the cover from the instrument panel fuse junction panel.

NOTE: On vehicles equipped with automatic transmissions, move the shift lever to the 1 position to ease removal.

Carefully press the (A) clips and remove the (B) steering column opening cover.

Postion the hood latch release handle aside.
Remove the screws.
Position the hood latch release aside.

Position the parking brake release handle aside.
Remove the screws.
Position the parking brake release handle aside.

Remove the lower instrument panel steering column cover (044F08).
Remove the six lower instrument panel steering column cover bolts.
Remove the lower instrument panel steering column cover.

Remove the two (A) bulkhead electrical connectors from the (B) instrument panel fuse junction panel.

Remove the two (A) instrument panel fuse junction panel bolts and remove the two (B) interior fuse junction panel nuts.

Disconnect the three (A) GEM/CTM electrical connectors from the (B) GEM/CTM.

Remove the three GEM/CTM screws and the GEM/CTM.


Installation

NOTE: When the battery (10655) is disconnected and reconnected, some abnormal drive symptoms may occur while the vehicle relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 mi) or more to relearn the strategy.

To install, reverse the removal procedure.
Check for proper operation.



Install the lower instrument panel steering column cover.
Position the lower instrument panel steering column cover.
Install the six bolts.

Install the parking brake release handle.
Position the parking brake release handle.
Install the screws.

Install the hood latch release handle.
Position the hood latch release handle.
Install the screws.

NOTE: On vehicles equipped with automatic transmissions, move the shift lever to the 1 position to ease installation.

Carefully press the (A) clips and install the (B) steering column opening cover.
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<!-- / sig --><!-- edit note --><HR style="COLOR: #d1d1e1; BACKGROUND-COLOR: #d1d1e1" SIZE=1>Last edited by Racerguy; 03-02-2003 at 11:39 AM.

 

Got the GEM off, took and hour plus. Where can I but this GEM. O'Reillys and Autozone do not know what it is. Dealer? NAPAs are all closed.

 

Caught the Ford parts guy at quitting time, bought his only one in stock -$270. Installed new GEM. Nothing has changed. No gauges, no idiot lights except seat belts and battery. Double checked all fuses and swapped them around just to triple check (swapped 5s with known working 5s and 50s with 50w).

Everything else still works.

Any suggestions.

 

Might seem like a stupid response but it could be the cluster is shot. Proper wiring diagram and diagnostics would be needed, or any other suggestions will be nothing more than a guess.
And of course we can only guess that you received the correct GEM.

 

Did you check F29 under the dash? It's the one that supplies the cluster along with F2 for the lights and electronics.

Steve

 

I am having the same problem with my 98. Speedo, tach, odometer,and all the other gauges not working. All the warning lights are ok.

I have checked the fuses and connections to the cluster.

 

I never did get my instuments working. I changed the the GEM but really there is no way Icould be sure that the parts guy gave me the appropriate part. But I would have thought something would have started working, even if the module was not the correct one for my truck.

I am still doing without. Been a long time since superbowl Sunday, the day that my instruments quit working.

I have not really considered changing out the instrument cluster. Seems like a lot of work and money to just perform more research and development work. The GEM changeout is difficult, but doable if you got patience and beer.

 

The instrument cluster is actually fairly simple to remove and replace(10-15 minutes), You can probably find a used one for a reasonable price at a local wrecking yard, The light switch must be removed to get to a screw that is located behind it which is probably the hardest part of the remove/install, There are three wiring harnesses that plug into the back of the cluster , Check these to make sure that one has not come loose then move on to the cluster itself.

If your cluster is bad you will need one from a 97 model year, If you can not find one with a tach you can use one without a tach as they are interchangeable.

My truck is a 97 and came with the standard cluster without tachometer, I wanted a tach and bought a cluster from a wrecking yard and installed it and it works perfectly , You must get a cluster from a 1997 if your truck is a 97 , The 97 and 98 both have analog odometers and look identical but they do not interchange as the wiring harness are pinned slightly differently(oil pressure gauge & coolant temp gauge).

The replacement cluster will most likely have different mileage on the odometer and you can either leave it without changing it, You can put your old speedo/odometer in the new cluster or the easiest is to change the mileage on the replacement cluster to match the one you are replacing, To change the mileage you simply remove the clear plastic front cover and using two small flat screw drivers reset the mileage to that of your original odometer, Using one screwdriver to seperate the number cogged wheels and the other to turn the one you need to reset, repeat this on each digit you want to reset.



Just a reminder here that your trucks actual mileage is stored on your trucks computer so keep this in mind when changing the mileage.

The computer will not upgrade the reading on the replacement cluster but when you go to inspection and they plug your truck into their equipment it may show the actual mileage stored in the trucks computer and they may question any difference shown on the actual odometer so I would not recommend setting to lower than your actual miles on truck. I would also recommend getting and keeping the receipt for the replacement cluster

Val

 

Ok, that is what I will do next.Thanks. Great info, would not of thought that the 97 and 98 were different.