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Unread 05-03-2011, 11:54 PM   #1
Canyon411
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Doors lock but won't unlock?

Trying to solve an issue with a 95zj. I can lock all doors and rear hatch by pressing the lock switch on the drivers door but pressing unlock causes the relay to click but none of the doors unlock. Same situation using the key-fob. Doors will lock with the keyfob, but pressing unlock causes clicking from the relay and no unlock.

Since the key-fob and drivers door switch both give the same results, a bad drivers switch can be rulled out. I would think the relay clicking is a sign that it is doing what it's supposed to (receiving 12v signal from the door switch/keyfob and energizing the coil therby closing contacts on the load side and sending power through. I could see one door actuator being bad, but not all of them, especially if they work just fine locking the doors....

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Unread 05-04-2011, 03:26 AM   #2
blackjack12982
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Subscribed, mine does this with the key fob...
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Unread 05-04-2011, 11:53 AM   #3
dodgedad94
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My locks are bass ackwards. I can unlock all the doors and hatch with the switch, but not lock.
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Unread 05-04-2011, 11:57 AM   #4
grego
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can you lock and unlock the rest of the doors from the passenger door in the front. I think that should do the 3 non driver doors and doesn't do the back one either.

that should tell you if the problem is somewhere close to the start of the system if you can do that and in the driver door region
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Unread 05-04-2011, 05:50 PM   #5
Foundrydude
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Broken wire in the doorjamb on the driver side.
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Unread 05-04-2011, 09:05 PM   #6
Canyon411
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I could see a broken wire in the drivers door causing the drivers door switch not to unlock any doors, but the key-fob has nothing to do with the drivers door and it will not unlock any doors either ....
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Unread 05-04-2011, 09:17 PM   #7
Foundrydude
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Most lock systems are kinda weird in that if there's a short/break anywhere nothing works. When I say anywhere I mean in each seperate side, lock and unlock. They're seperate DC circuits in terms of wiring and troubleshooting. If unlock is working the system's ground & power is OK but there's a short/break in the lock side wiring or switch gear.

Also my 95 had the same thing happen and was fixed by soldering a broken/stripped wire in the jamb. Bout the fifth vehicle that's done it to me.

good luck
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Unread 05-04-2011, 11:12 PM   #8
Canyon411
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Quote:
Originally Posted by Foundrydude View Post
Most lock systems are kinda weird in that if there's a short/break anywhere nothing works. When I say anywhere I mean in each seperate side, lock and unlock. They're seperate DC circuits in terms of wiring and troubleshooting. If unlock is working the system's ground & power is OK but there's a short/break in the lock side wiring or switch gear.

Also my 95 had the same thing happen and was fixed by soldering a broken/stripped wire in the jamb. Bout the fifth vehicle that's done it to me.

good luck
Hmmm, now you got me thinking .... (not ALWAYS a good thing.) I checked the passenger lock switch and same result as the drivers switch and keyfob. Any one of these can trigger the (all lock) function, but none of them will trigger (all unlock), although it seems like the intention is there because the relay clicks like it's trying to unlock the doors. Anyone know if there are seperate relays for lock and unlock? If so, I could try swapping them and see if I can get (un-lock) to function.

I will also investigate the harness in the doorjam to see if any wires have frayed or broken as well.
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Unread 05-05-2011, 12:53 AM   #9
Canyon411
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Did some forum searching and found a post concerning pre-1991 xj's, but the power flow is interesting and it seems to indicate that all lock/unlock circuits flow thru the drivers door master switch before seeing ground.

Here is an exerpt from that post....

I have the factory service manual, so I have been able to trace everything. I have keyless entry w. remote, which has two relays in the passenger side kick panel. Power goes to the master switch on driver's door and to the passenger door switch. Power also goes to the keyless/remote relays. I had 12.4 volts going into all those relays and switches. The ground path is through the driver's side master switch then to the body ground. All pwr and the ground flows through the passenger side switch to lock or unlock the door locks regardless of whether you use either of the door switches or the remote/keyless/relays (i.e., the remote signal triggers the relays).


.... If the zj wiring follows some of the same logic, perhaps a bad/broken wire in the drivers door harness could be preventing the (unlock) side of the system from seeing ground. That would also explain why I can hear the relay clicking (doing it's job) yet no unlock function because the ground side of the circuit is not being completed.
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Unread 05-05-2011, 11:05 AM   #10
impuresoul2k3
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Quote:
Originally Posted by Canyon411 View Post
Did some forum searching and found a post concerning pre-1991 xj's, but the power flow is interesting and it seems to indicate that all lock/unlock circuits flow thru the drivers door master switch before seeing ground.
Correct, same way on the ZJs
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Unread 05-06-2011, 08:22 PM   #11
Canyon411
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stopped out at the recking yard today and got a close-up look at the door harness on several zj's. It was mind-blowing to see wires hanging together by single strands (insulation completely gone) and other wires completely broken apart and floating with-in the rubber boot. There is a bolt that secures one harness end to the door and (thru the gromet into the inside), a pair of connectors that could be unpligged to completely remove and replace the whole harness. That sounded good until I imagined what a dealer would want for a replacement harness if they were still available. I am going to take mine apart soon and see how bad the carnage is. I am expecting to find my problem with un/lock is from a broken wire. I will update this post as I get in there to take a look.
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Unread 05-25-2011, 09:24 PM   #12
Canyon411
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I thought I would follow up on this thread with the solution to my problem in hopes that it will help others find a solution for similar problems. It was suggested early in the thread that the drivers door jam harness may have a broken wire.

I was able to inspect the wires with-in the boot (between the drivers door and the door jam) finding serveral wires with brittle chaffed insulation and one wire was litterally staying intact by a single strand of copper. My project (as soon as time allows) will be to replace several of these wires either by cutting out the bad sections and addding a filler piece, or if possible, rebuilding the harness from end to end.

I havent fixed it yet but it feels good knowing what the issue is and what it is going to take to fix it.
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