Its an F150 , 1999, 4x4 Lariat, flairside.
As soon its started raining, the radio turned off and the 4x4 light blinks ???

If I shift to neutral the radio turns "on", them I switch to drive and its turned "off". This happens only when it's raining.
Is there any electrical conector, plug or device I should verify???

Any advise?

Thanks

Ben

 

Check for water behind the cab fuse panel.

There have been cases of where the windshield leaks in the lower left hand corner of the windshield, and it drips on the GEM.

The GEM is bolted to the back of the cab fuse panel.

 

I'm having the same issues on my 03 supercrew. Only the windows don't work in gear also. It rained last night and now I have a puddle in the floor and electronic issues. Should I just let the GEM dry out and it will be fine? How can I seal the winshield to keep this from happening again? Thanks in advance. I would search for the answer but I'm on my junk phone.

 

I'm drying out the fuse panel with a fan, and the windows and radio work again but the AC stays on after the key is off. Any ideas, Is this related to the GEM getting wet?

 

Does any HVAC setting run after the key is off ( not just the AC ) ?

Could be a case of a problem with the blower motor relay. If you put the function selector switch in the off position, is the blower still running ?

The solution to the windshield is to have it removed, the channel cleaned out, and reset in new sealant.

 

the HAVC system would blow on any ON setting, but everything is working normal now. I'll have the windshield resealed, but is there anything I can do to keep the GEM from corroiding after getting wet?

 

Some members have reported after drying out the cab, and resealing the windshield, not having a problem again. Seems the repetitive cycle of wet dry is what causes the problem. Once it stays dry it might work fine.

The only way to know for sure is to remove the passenger compartment fuse panel, unbolt the GEM, clean the contacts, and reassemble. Right now I woudl focus on the windshield, and keeping it dry and see what happens.

Either you would have a 800.00 bill at a dealer for this ( they replace both the CJB and the GEM ) or spend a few hours with a DIY to clean them.

 

Its dry and in the garage until I get the windshield fixed. I'll pull the fuse panel out and try and clean the GEM. Any pics of the GEM-contacts that I need to check, or advice to make it go smoother? Can I use alcohol to clean them, and dielectric grease afterwards?

Thanks

 

Don't know the specific pins, when you un bolt them, just check any for green corrosion.

91% isopropyl rubbing alcohol would work fine, maybe a typewriter eraser if you have one. any thing that will not change the dimensions of the pin too much.

dielectric grease cannot hurt.

I'll drop you an email via your profile so I can email you the pdf I have for the 1997 GEM removal. Things might look a bit different, but it is a good starting point.

 

thanks a ton man.

 

I have a 2002 F-150 XLT.

I have this same problem. I fixed the windshield leak and replaced the GEM module - $ouch$. It worked fine for 1 day and now the radio still shuts off when in reverse or drive. I was having problems with windows and wipers but now they seem to work fine. Sometimes the radio works when in drive and sometimes it doesn't. Any thoughts?

 

Have you had a lot of rain, or washed the truck as of late ?

The starting point I can think of, is to make sure the windshield repair was done correctly, by checking for water damage.

The repair, was it a new Central Junction Box, or did they reuse the old one ? ( sounds like they reused the CJB, just want to be sure )

 

Well, the new GEM module was just installed yesterday and we have not had any rain since then.

Is the Central Junction Box something different then the GEM module?

I just drove it and it has all of its old symptoms still - radio, 4x4 light, windows, windshield wipers etc.

Thank you for your ideas.

 

Central Junction box is the cab fuse panel attached to the GEM.

 

I ended up taking it in to fix the problem and it was the transmission range sensor.