Hey, most of the electrical on my '87 SR5 Turbo that I picked up last weekend works fine. The power windows work fine, but the power locks have stopped working all of a sudden. When I press the lock button, I hear a faint click in the Passenger kick-board - maybe a bad solenoid.

Any ideas? I'm new to power locks.

Thanks.

 

Sounds like you're just guessing.

The Door Lock Control Relay contains, among a lot of other stuff, a relay. That's what you're hearing.

The Locks themselves are driven by solenoids, are much louder than any relay, and (duh!) are in the doors.

The most likely failure point is the switch in the armrest. Looking at it won't help at all; the electrons are just too darned small. Use your multimeter, and the problem will be easily found.

 

Yes, I’m guessing. The solenoids seem to work fine. If I manually force both doors Locked, then press the switch, I can get both to Unlock on their own. But I cannot get it to lock/unlock via the switch.

I’m not great with a MM. what should I test on the armrest switch?

 

Have a look at your FSM body electrical section, it will tell you which pins have continuity in which positions. It also specifies the test procedure for the door lock solenoid.

If it works in one direction but not the other its could be the switch, the solenoids, or even lack of lube on the mechanical linkage. You'll have to check them all but start with the switches because they are the easiest to get to.

 

http://web.archive.org/web/201106261.../8powerdoo.pdf

You have an electrical problem. Either get "great" with a multimeter or take it to someone who is. There is no easy way around that. With post-1950s cars saying "I'm not great with a multimeter" is the equivalent of saying "I'm not great with wrenches."
http://www.cygnusx1.net/Media/Supra/...otaTech/h4.pdf

 

Yes, i’ve Confirmed that I can Unlock with the switch if I manually Lock it. But I cannot Lock with the switch.

Also, probably nothing but it looks like the switch has two prongs in Upper Left but wiring only has one Blue with Red stripe wire. Surely i’m Not kissing an entire wire though.

 

I think I found the problem...

 

Ok, I fixed the contacts and now the lock switch seems to work as it should. Unfortunately that didn’t fix the door locks - still will not lock or unlock on demand.

As mentioned, the locking motors seem fine as I can Unlock both sides after manually Locking.

Each time I lock/Unlock with the switch I can hear what sounds like a relay in the pass kickboard, so that seems fine.

Any ideas?

 

Sorry... I'm confused
The lock switch works but you cannot lock or unlock on demand? Don't you use the lock switch to lock or on luck on demand?

Let's back track:
Please help us clearly see what you have right in from of you...
We are only talking about door locks now, correct?

Please re-list what work and what do not work at present.
I am newer to power locks than O.P. because I have a dlx.
Specify whether you are using:
The master lock switch which is at driver controls that lock and unlock ALL locks,
OR the individual lock switch at driver's side for the driver's door only,
OR the individual lock switch at passenger side for the passenger side only.
Remember, I do not have power locks on my truck so I do not know what it looks like on yours.

If you are ready to take some voltage checks, schematic for power windows/doors courtesy of SomedayJ is below. If only door lock is the problem prioritize points A, G, G1, H, H1, J and K.

 

The power window lock controller is located behind the driver's seat. What you are hearing is the passenger side solenoid, most likely. You'll have to get in there and check the linkages.

Is it both locks that aren't locking or just the passengers?

There is a single door lock switch for the front doors located in the driver's door, the passenger side only has a power window switch.


Left to right, passengers window, drivers window, passenger window lockout, door locks.

 

Problem Restated: The Master power door lock button (drivers side door panel) do not do anything to either Drivers or Passenger locks if doors are unlocked by default. Here are the symptoms:
a) If I press the Master driver door lock switch, I can hear the passenger side solenoid making a clicking noise but no moment on locks
b) If manually force either/both door lock to lock position and press "Unlock" on the master driver switch, Both Drivers and Passenger doors Unlock automatically
c) The Female Connector in the wiring has two prongs in Upper Left, but male insert wiring only has one wire (Blue with Red stripe). Surely it's not missing a wire to the male insert though, but not used to seeing a female connector without a male counterpart.

That's all I know at this point.

Potential next step:
1) Attempt to follow the schematic above with a multimeter

Hopefully this helps.

 

 

Ok, i’m still trying to fix this. I took a video (attached). I traced the clicking sound to Door Control Box In Pass Kickplate. The door lock switch is sending a signal to the Door Control Box fine but then the signal doesn’t go to the door locks.

Again, if I lock the doors by hand, I can Unlock with the switch. But if the doors are unlocked, I cannot lock.

Using MM and Test Light with schematics above next.

 

As suspected, I’m getting the signal to the Unlock (Black wire White stripe) at the door but no signal to Lock (solid Black wire). Per the troubleshooting section of FSM, looks like Lock is accomplished by + and - swapping. Which is odd since Unlock works but Lock does t.

is there something between the Lock Door Control Box and the Lock Door wiring? I don’t see any fuses.

 

I read some of the runs could be bad on the Lock side of the DoorControl Box. Pic below - does anyone see anything?

 

Maybe I need to solder the one in the middle that doesn’t look like the rest.

 

Check here (red circle):

 

Yes. (At least, it can't hurt.)

 

Fixed both spots to be safe. No change! I’m a novice at soldering, but it’s hard to screw it up - expose wires, wet/clean tip, add solder, let cool.

 

Found one more iffy connection and Soldered it to be safe. THEY WORK!!!!

thanks everyone! Love having door locks again!