fj62 power lock problems (1 Viewer)

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I am new to this forum, although I have been lurking for some time. Can someone explain the operation of the power door locks on an FJ62?

My power locks don't work.

To diagnose the problem, I checked the voltages at the wiring harness that plugs into the lock/unlock switch on the driver door. One day I have voltages there, other days I don't. Before solving this problem (let's leave this for another day), I wanted to check the solenoids (?, actuators? not sure of the correct name) to make sure they are working (because even when I have power at the harness, the locks don't work). I figured I would work my way from the solenoids backward.

To test the solenoids, I disconnected the wiring harness from the solenoid (?, about halfway down the door, vertically below the outside handle) in the driver door and applied 12V across its two terminals. I hear a slight clicking-like sound. But, the sound does not come from the solenoid, it comes from near the inside handle. Is there another component behind there that is part of the lock/unlock system? I figured that the system just had four solenoinds, one at each door, somewhere below the outside handle. Am I wrong?

Could someone explain the lock/unlock system to a newbie willing to learn?

I have found some other posts, but they are not quite basic enough.

Any help would be appreciated.

Thanks.
 
The power door locks on these rigs are a bit of an adventure. There are five solenoids that actuate the locks in the 4 doors and the rear hatch. Each solenoid is connected to rods and pivot points so that in one position the doors are locked and in the other the doors are unlocked. With the inner door panel off, you should be able to manually lock and unlock the doors and watch the mechanism in action. There should be no binding. You will want to shoot a little lithium grease in all the joints to make sure the rods operate smoothly by hand. Now if you disconnect the solenoid wires as you describe and apply 12v to the solenoid at the connector, you should be able to lock and unlock the door by reversing the + and - from the battery at the solenoid. Either run long wires from the battery, or use a spare battery as your power source. A solenoid is activated by current, so you need to make sure that your test setup can deliver adequate current to the solenoid to make it jump. Once you have tested your solenoids and they all work, you can troubleshoot the rest of the system. If you have to replace any solenoids, get one from a used parts source. They are spendy to buy new.

Electrically, there are four wires that go to the switch in the drivers door. I will refer to the color of wires from the connector on into the vehicle. With the exception of the White/Black wire, the wires from the connector to the door switch change color. So, at the vehicle side of the connector, and with the switch disconnected, there are four wires. A red one, a blue/white one, a blue/red one and a white/black one. As I recall, the second color is the color of the stripe that runs the length of the wire. Regardless of the position of the ignition switch, there should always be 12V on the red wire. If not, see the link in the previous post by austinmark to try resetting the circuit breaker. Once you have established that you have 12 volts on the red wire, install a short jumper wire between the white/black wire (which is ground) and the blue/white wire. Now with a short jumper wire, momentarily connect the red wire to the blue/red wire. The doors should UNLOCK. Now you can test the lock functionality by moving the jumper between the white/black wire and the blue/red wire and momentarily connecting a short jumper between the red wire and the blue/white wire. This should make the doors LOCK. If one or more doors don't lock or unlock, then you need to check wires and connectors to figure out what is wrong. A previous owner may have screwed up the wiring in a lame attempt to fix it, or you could just have a dirty connection or broken/cut wire. Use some electrical contact spray cleaner in all the connectors.

Once you have everything working at this point, you are ready to tackle the switch. In my experience, the switch is inadequate for the amount of current required to activate the solenoids, so I engineered a relay solution which I will point you to in a minute. If you remove the switch from the door panel and carefully disassemble it, you will see lots of black around the contacts. It will look like there has been a fire. Well, in fact there has been. That black soot is from the switch contacts arcing. So take some rubbing alcohol and clean up the black grime. Then take some fine emery cloth and polish up the contacts until they look smooth and most of the pits are gone. If you put everything back together, your door locks will work great and you will be smiling ear to ear--BUT IT WON'T LAST! Within a few lock and unlock cycles, the problems will begin to return. I believe that the metal contacts had a hardened surface when they were new. Once that hard surface is eroded by the arcing when the switch is opened and closed a million times, the softer metal is exposed, and it doesn't matter how many times you polish the contacts, the softer metal will begin to pit immediately. So, you need to install a permanent fix where the heavy current switching is done by relays, and not the door switch. Follow my thread here for this fix:

https://forum.ih8mud.com/60-series-wagons/261058-power-windows-door-locks-permanent-fix.html
 
I also think the switches were weak points in the system,esp. the drivers side master.Look or another master switch. Mike
 
i have to lock and unlock my doors like 6 times before the rear driver door unlocks. ive just goten used to it. good luck finding whats wrong with it.
 
Thanks to Austinmark for hitting the nail on the head. Resetting the circuit breaker did the trick. I will add a paper clip to the "toolbox."

Thanks to slcfj62 for yet another very detailed and insightful response. How awesome to have forums like this, and contributors like you. Thanks again for taking the time. Although resetting the circuit breaker worked, I am sure your description will come in handy soon enough.

Michael Hanson and kmf88 thanks to you guys as well.
 
Should 12volts be present at the connector of the rear doors' solenoid when pressing the master lock button?
Im reading less than 6 with the engine off.
If so, is it the switch that is causing the low voltage?
 
i have to lock and unlock my doors like 6 times before the rear driver door unlocks. ive just goten used to it. good luck finding whats wrong with it.

Same here. I just sprayed down every joint in there with some silicon/Teflon lube (the DuPont stuff) and that helped it, but it still takes several hits before the lock moves if it's cold. I've already done the lock relay mod, so I assume (still need to double check) there's full voltage getting to the solenoid. If there is, my most likely option is either a loose connection perhaps, or the solenoid itself is getting ready to tank. If the latter, I'm going to see if I can rebuild it at all. Don't expect to be able to, but for s***s and giggles it could be interesting.
 
That's not a good sign. You did the mod and it still doesn't work?
That's what worries me.
I'm planning on doing the mod and was hoping it was the final fix.
The mod looks good but has 2 major weaknesses. One, the 12v supplied to master switch may not be strong enough to power the locks, even with the relays. 2: the wiring between the master switch and the power locks may be old and full of resistance.
 
That's not a good sign. You did the mod and it still doesn't work?
That's what worries me.
I'm planning on doing the mod and was hoping it was the final fix.
The mod looks good but has 2 major weaknesses. One, the 12v supplied to master switch may not be strong enough to power the locks, even with the relays. 2: the wiring between the master switch and the power locks may be old and full of resistance.

All the other locks act as if they're going to tear their way through the door sheet metal after doing the mod, so that's what has me thinking that either the solenoid itself is bad or going bad, or there's an issue with corrosion or something like that with the connector in the door.

Hopefully this weekend I'll have a little more time to troubleshoot it.

The mod actually taps into a 12V lead that sends the 12V through the relays to the solenoids, bypassing the resistance that gets introduced by the switch. The switches act as only switches to trigger the relays after the mod. No more high amperage going through them.
 
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Hey guys & gals, this is my first response. I just read all the above and have 1 question: where are the door lock relays? I found the relays for the rear hatch, and am now looking for the others. Thanks.
 
Hey guys & gals, this is my first response. I just read all the above and have 1 question: where are the door lock relays? I found the relays for the rear hatch, and am now looking for the others. Thanks.
There are no relays for the door locks. The master switch on the driver's door carries all of the current for the solenoids. The mod in question adds two relays to the circuit in order to take the load off of the switch. If your switch is old and has buildup on the contacts (from repeated electrical arcing) like I guarantee every factory original switch does by this point, you'll notice a difference after the relay mod. Now if you've installed a new switch recently (Switch Doctor makes a good quality replacement, though it's only available in brown and according to them, no plans to offer a unit in gray), you won't notice any improvement by doing the relay mod. Reason being that the contacts in the new switch are clean and will take several years to accumulate enough buildup to cause a problem themselves.
 
There are no relays for the door locks. The master switch on the driver's door carries all of the current for the solenoids. The mod in question adds two relays to the circuit in order to take the load off of the switch. If your switch is old and has buildup on the contacts (from repeated electrical arcing) like I guarantee every factory original switch does by this point, you'll notice a difference after the relay mod. Now if you've installed a new switch recently (Switch Doctor makes a good quality replacement, though it's only available in brown and according to them, no plans to offer a unit in gray), you won't notice any improvement by doing the relay mod. Reason being that the contacts in the new switch are clean and will take several years to accumulate enough buildup to cause a problem themselves.
Thanks for your response. All my solenoids and locks are working great (had fj62 5 months now). I’m attempting to install a keyless remote just for the door locks.
 
Thanks for your response. All my solenoids and locks are working great (had fj62 5 months now). I’m attempting to install a keyless remote just for the door locks.
It's been a while since I got in depth with the keyless systems, but I believe with most you will still need to add the two relays. I've been told that some keyless kits have relays integrated into the unit though, so depending on the kit you get, that might simplify it.

The kit I have (and still have not yet installed) does NOT have integrated relays as far as I can tell.
 
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I bought a 1990 FJ62 with some power lock issues. I popped the panel to find this. Is this the relay mod or some other trash?
 

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