radio and window issues-no power

lariat 7.3 · May 12, 2015

working on my cousins truck at the moment, my buddies truck also does this.

What happens is you'll be cruising around and all of a sudden the radio will shut off and the windows quit working. Somtimes they'll fire back up in a couple minutes, sometimes they won't. He has already replaced the relay a couple times and said it helped a bit. Hasnt had the issue come up for about three months. Just started happening again.

When it happens on my buddies truck, there is a little red light that continues the blink on his aftermarket head unit whichs leads me to believe its still getting some type of power still, prob the keep alive memory function.

Has anyone actually had success tracking down this issue?

cbf9703 · May 12, 2015

Mine was bad GEM module from a leaking windshield seal.

ToMang07 · May 12, 2015

cbf9703 said:
Mine was bad GEM module from a leaking windshield seal.

^That would be my guess as well. Still, check fuses, and replace if you have spares just to rule that out.

lariat 7.3 · May 14, 2015

Any definitive way to tell the gem is bad

blaze42069 · May 14, 2015

Interesting on the gem module. I have the same issue in a 2002 f350. I was told it was a relay in the speedo cluster that needs a new cluster to fix or send out for repair. I was told it is the relay that keeps the radio on and windows working when you turn off the ignition before you open the door. Your interior lights should not work either when the windows and radio quit. It happens every now and again. I just hammer down on the dash above the cluster and it has worked until yesterday when it was hot outside. But this morning worked again no problems........yet.:cursing:

Arisley · May 14, 2015

7.3 fleet mechanic should know what's up. There is no relay in the dash cluster. Just look at the wiring diagrams.

lariat 7.3 · May 14, 2015

I just read on a Facebook page that there's an issue with the cluster that will cause these exact problems

co04cobra · May 14, 2015

2 different animals. 99-01 have GEM modules that can cause weird electrical issues like this.

Starting in 02 everything is a integrated module also built into the fuse box.

lariat 7.3 · May 15, 2015

So any ideas on the later model 7.3? Both are 03 that are doing this, one has already had a couple relays

Arisley · May 15, 2015

lariat 7.3 said:
So any ideas on the later model 7.3? Both are 03 that are doing this, one has already had a couple relays

co04cobra said:
2 different animals. 99-01 have GEM modules that can cause weird electrical issues like this.

Starting in 02 everything is a integrated module also built into the fuse box.

There is the answer.

htrotte · May 17, 2015

I have been told it is a microprocessor in the instrument cluster. That's where i get when trying to troubleshoot. Only way to fix is replace the cluster.

TyCorr · May 17, 2015

Gem is on the back of the fuse panel in 99-01s. I dont know where the body control module is on the late 01-03s. Co04cobra said its on the back of the fuse panel. I eas under the impression it was in the center of the dash, behind the radio...but I dont know.

I can show you where the majority of them leak because I have one tote apart to see if the windshield is leaking.

co04cobra · May 17, 2015

99-01s have a GEM bolted to the back of the fuse box.

02 started a integrated fuse box that was in the same place as the 99-01 fuse box, but no more GEM. Behind the radio is the VSM. It can also cause some odd electrical issues.

02 was also the first year radio shuts off with the door open which is controlled by the VSM. The VSM and fuse box work together on some of this stuff, so in my experience it can be time consuming to track down.

If its a 02 X.L. truck you have a HEC controlling the radio off with the key off and door open function.

I am not saying in 02 its impossible for the cluster to cause issues. It has been a while since I was chasing a problem on one of these and studied the schematic.

You do not have to have a new cluster from the dealer if that is the problem. A used one from similar type truck as yours from a 02-03 7.3 will work.

The 05s have a cluster problem that causes a lot of the same issues you describe and they still have a VSM.

lariat 7.3 · May 17, 2015

So VSM is probable cause? He used to be able to hit the dash above the radio and everything would fire back up

Pstrke96 · May 18, 2015

My 02 radio/door function doesn't work or my overhead display. Potentially 2 separate issues. Also my interior/cargo lamp stays on like 17 minutes after doors locked. Interior lights might be a door trigger but the rest hasn't bothered me enough to chase it down. Just a work truck.