Hello all! So I have been having a bit of a issue with my 01 f250 7.3 for the past week my battery light has been flashing, I suspected my alternator was going out, but before I just swapped it out I checked all the connections and snugged the power wire on the alternator, put my brake controller to the voltage monitor mode and it quickly climbed to 14v and the battery light quit flashing. 👍 but then I get home after a short drive and my door ajar light is staying on, so I search the forums and discover it’s a common problem and some wd40 may fix it. Soaked all the latched with wd40 slammed all the doors for about 1.5 hours and still the light stays on... hopped in for a little drive and notice when I buckle up the doorajar light goes off... unbuckle it door ajar light comes on along with the dome light.. buckle and unbuckle numerous times it’s looking like a party in the cab the dome light is flashing like crazy... continue to mess with the driver side door latch looking for a wire that’s shorted but can’t find anything... do you guys think it could be the GEM module?? The only reason I think that is because the cruise and horn doesn’t work and the owner before me converted the electronic 4x4 to a manual 4x4 lever because the ESOF has failed... I can’t help but wonder if the GEM is failing causing the door ajar issue and the cruise and horn problem? Thoughts? Should I just replace the latch first to see if that’s the problem... I would guess it’s the driver doorsince the other 3 doors don’t open too often and I was by myself when this door ajar light started?? I pulled the dome light and unplugged my brake controller to try and preserve my batteries! Thank you all for your help!

Brock

 

GEM is not a cheap item to throw at a problem. I would rule other things out before replacing it.

Your horn and cruise issue is normally a clockspring issue so I would not lump it in with the door ajar/seatbelt issue.

There is always the possibility that the fluctuating voltage could have damaged the GEM or its programming.

Have you tried disconnecting the battery (batteries) and letting the truck sit for awhile? This will reset everything so you can start from scratch.

You can also check the connections on the GEM module to make sure they are clean and solid (it is located behind the fuse box). Use some electronic cleaner in the connector(s).

I'm not sure how long you've had the truck but there is also the possibility that something was done when removing the ESOF that has finally surfaced. I would think it would be less expensive to replace parts on the ESOF (switch, transfer case modue, cap off the vacuum lines) instead of doing a full conversion.

 

The vast majority of the time, ESOF is abandoned due to vacuum issues, not the GEM.

 

I have only owned it for about 4 months really has been a great truck for the short time i have had it and tows my travel trailer pretty well... i will unhook the batteries now and see what happens after that... it just seems like something has went berserk, being the correlation with the seat belt...

 

I had and 2002 f150. Not sure if you have the fuse box in the bottom left where your left knee is.

I had some wierd **** happening with mine electrical and found a used gem module and swapped it out. Seemed to help for a while but some of the wonky **** came back.

Found out my battery saver relay was getting hot as **** and the dome lights were acting strange with somethings with the lights and headlights when I locked it etc.

Changed that relay out never had another issue.

 

Really weird situation, I decided to go out and disconnect the batteries for a few hours to see if that would reset everything and let me start from scratch... just before I disconnected them I figured i would start it and see if anything else was acting weird.... lo and behold the damn thing is working normal... door ajar light goes off and all is well except the battery light is still coming on while driving... i know its only a matter of time before this issues creeps back up on me, I cant help but wonder if i have a alternator or battery issue because that light is still coming on and off while driving ill take those in for a test while I'm at it!... I may look for and change the battery saver relay just because...

Thank you guys for your help!

 

The only time my battery light has come on has been due to an electrical connection or alternator/voltage regulator issue.

You can pull your alternator and have it tested at an auto parts store to confirm.

 

I did have to change a set of battery cables out before. They started corroding internally from the battery post end.

Try taking your cables off and clean and sand them. You can get coorsion that is hard to see. Took me a while to find that problem.

I ended up cutting the insulation back and the cable was in terrible shape.

Never had another issue after. Some baking soda or that battery terminal cleaner works. The cleaner turns either yellow or red when it contacts acid. Wear eye protection.

 

You can also bend/flex the cables to see if their still pliable before you cut the sheathing back. If you get to a section that is hard to bend (or doesn't bend at all) that is signs of internal damage/corrosion.

 

Excellent I did not know that.