robertsredfx4

I have a 2005 Crew Cab FX4 with a driver side power door lock problem, any suggestions on a fix would be appreciated. Here's the problem....

The power door lock on the front driver side will lock the door locks, but will not unlock them. When using the passenger side controls or the keyless remote, the locks work fine, they lock and unlock perfectly.

I have already tested the driver side toggle switch by swapping the switch with the passenger side, and the problem remains the same, so I know it's not a switch problem.

If the driver toggle switch is hooked up to the passenger side, the switch works perfectly. If the passenger toggle switch is hooked up to the driver side, the unlock will not work once again.

The locks are not binding in any way as when using the passenger side switch or the remote, the locks go up and down very quickly and sound very strong.

The problem happens with the ignition on or off.

Any sugestions???

Thanks,

Mod (Ret.)

The unlock wiring on the drivers side switch harness must be "open". You'll want to used a cheap test light or volt/ohm meter (better) to check the unlock wiring from the switch to the unlock solinoid. I don't have my wiring schematic handy to give you the color code(s) for the drivers side "unlock" wiring, but you should be able to figure it out when you remove the drivers side door panel (required).

csaw454

How did you fix this problem? I am having a similiar issue, but with both unlock buttons. The lock buttons work fine on both doors and the remote works as well.

Thanks!

MPD

I am in the same boat... any suggested help?

MPD

checked the fuse panel... no blown fuses.

Tried switching the passenger & driver side switches. NO LUCK.

homer

No aftermarket remote start or alarm that you know of? Just ensuring it's not a cause of a broken wire due to installation. Could be different for each of you though.

broderp

Has this issue been resolved?

If it's just the unlock that's not working and it's only on the drivers side then this leads me to believe it's a break in the harness.

I'm not sure how different the 05 is from the 04, but the 04 switches are in parallel with one another, This means that pulse for unlock (and lock) reach the BCM via the same wire(s). Meaning the BCM only has two inputs from the switches, one for lock and one for unlock.

So if one side works fine, the problem has to be before the splice in the harness going to the switch.

Given the facts the OP posted, there's not much else it can be IMO. It also would explain why the remote works as I don't believe the RF signal comes from the switch wires.

If your up to it, one you locate the wire that is for the unlock ground signal, you can test for continuity from the switch connector all the way to the BCM. You can also check for continuity between both switches "unlock" wires. If I'm correct you will not have continuity.

A quick fix (if this proves to be the issue)would be to run a wire from the drivers "unlock" wire to the other sides "unlock" wire. This may be quicker than tracing a wire thru the harness from the door to the BCM.

Post what you find.

Liscomb21

I have got a theory . Same thing was going on with my truck when I got it but mine was the windows . The wires that run into the doors on these trucks are cut too short and after a while they will get a little brittle and break . What I did was open my doors and pull back the black rubber wire covers and check all the wires and more then likely you will find your culprit I just used some wire splices with the heat shrink ends to put them back together . I only had problrms with the drivers door and rear drivers door .

broderp

That would make very good sense. I saw a YouTube video that said and showed the exact same thing.

Robert Clark

Thank you for the information to check the harness between door and cab. The wiring for doors appear to be clip type connectors and mine was broke off at the revealing of the wires. See the picture. Check there first fellas!