Hello all!

I've got a 2001 F-250 7.3l PS. The power door locks and power mirror adjustments are not working (I mention both in case a module that controls both could be involved). All 4 windows roll up and down fine with any of the switches. The truck does have keyless entry, and will sound the horn after double tapping the lock button on a fob, but the locks do not move at all and I hear no lock/unlock relay clicking. Neither the driver or passenger unlock/lock switches will work either. I hear no relay noise, click, etc and the door locks do not move at all. In many cases it appears the actuators fail, but because I am not hearing the relays under the dash click and the locks do not move at all, I would like to believe that isn't the problem.

I have tried replacing the relays to no avail. I tested the relays outside of the truck and they appear to be functional. This makes me think the issue lies in the wiring between the switch(es) and the relay(s), or a module somewhere in the mix. I also switched the passenger side switch to the drivers side, but no luck there either. I attempted jumping the wires that should send signal to the relays for lock/unlock, and that didn't work either (possible I wasn't doing it correctly- I'm no electrician).

Any help here would be greatly appreciated. I did my best researching and looking at the wiring diagram, but I can't figure this one out.

Thanks in advance!

Jakob

 

Almost a decade ago, I had the same (major) symptom on my 01. After spending time poking around the relays, I finally figured out I had simultaneous failures of both lock actuators. I don't recall offhand whether or not the relays were making any noise or not. Since they're buried way up there on the firewall behind the radio, they're quite the pain to access.

BTW, did you first check fuse F26 under the hood to make sure it's passing power? If the PARK lamp relay doesn't flash those lamps when the fob is activated, you've probably lost that power feed.

In any event, the four relays on RKE-equipped trucks are controlled by signals from the GEM module. If the GEM isn't fully operational, then neither will the door locks.

Sounds like you have the schematics. Do you also have the pinpoint diagnostic routine?

 

So, when using the lock or unlock on either of the two fobs, the PARK lamps do NOT flash. I checked F26 (20A) and it appears good, and is passing power (~12v on both sides of the fuse at all times). I did swap that fuse with another for giggles, and of course still having the same symptoms. When I hit the fob- I assume the GEM would be the first thing that signal hits, correct? If so, I think I may have a bad GEM on my hands, or possibly some of the wiring to/from it.

I believe I have the correct schematics-- it is a crew cab truck. As to the pinpoint diagnostic routine, I would appreciate it if you're able to point me in the right direction there as I don't have it. Regardless, I think I'll be taking a look at that GEM and cleaning connections up and reseating the cables.

Thank you!

 

Yes, the RKE receiver is integrated into the GEM.
I'd consider it premature to assume the GEM is bad. Could certainly be bad, have a bad connection or wiring fault, ..... or not. Inspecting and reseating the GEM connectors is certainly an appropriate first course of action. You might see the cause of the issue; for example - water damage.