Hey guys,

I've got a weird situation that doesn't seem to match any of the searches I've found about locking.

0. The passenger door acts fine all the time and has been closed during all tests.
1. Driver door open and try to lock the doors, the actuator tries to do it's thing and of course it won't lock because the door is open.
2. Driver door open, turn the latch on the end of the door to the closed position with my hand (like it would be with the door closed), the system locks both doors as if both doors were closed. Everything works fine.
3. Close driver door and lock with key, only the passenger door tries to close, the actuator on the driver door is not being turned on at all. Open the door again and do test #2 above immediately and the actuator on the driver door works fine and both doors lock.

It only appears that it fails if the driver's door is in the closed position. Is there some type of current that runs through the striker plate and/or the latch mechanism that would cause this or could it be the door switch that turns on the lights inside the car?

Things I've tried:
I've checked fuse #12 and it's good
I have the driver's door actuator out of the car, but hooked to the electronics and it will work just fine with the door open and the latch in any position, but is not actuated with the door closed.

Any ideas?

Thanks,
Jim

 

I'm not that familiar with the pre-91 lock/alarm system, but I will give you a few suggestions. On test 3 you say, the passenger door tries to close, does it lock? What do you mean by tries?

On test 1, how are you attempting to lock the doors?

I find it strange that when you lock the driver door with the key, it does not lock. Do you feel resistance when you turn the key? I assume the LED button is not moving either when you turn the key?

No current runs through the striker plate, but the light sensor switch at the front of the door is used by the lock/alarm system to know if the door is open or closed, that could be something to look at. If you give me a little more information I may be able to assist you more.

What happens when you are in the car with both doors closed and you try to lock the driver's door (with the turn **** and/or with the center console button)?

I just recently posted (within the past 3 days) a lot of information on the lock/alarm system. The problem is I don't know if the pre-91s work the same way as the post 91s as the controller was changed.

 

Hey CabrioArtie, I've answered your questions in-line below, but have found out the following since posting this morning.

1. I have verified that the micro-switch on the driver's door is functioning because it always tries to lock passenger door no matter what when I use the key in the driver's door.
2. The problem locking the driver's door is intermittent at this point. After I close the driver's door, sometimes both doors will lock correctly and other times not, both when using the key in the driver's door or from the central locking button. I removed the door handle, cleaned 20 years of buildup off of everything, tightened the phillips head screw at the end of the tumbler/lever and routed the micro-switch wiring back as it should be. Evidently this problem has been there for a while because the wires were routed incorrectly and held down with some sort of goo.
3. Since you've confirmed that there is no current of any kind that runs through the locking assembly or striker plate, I really think that the actuator is starting to quit working from the shock of closing the door over time.

Please see my comments below and I'd love to hear any thoughts that you might have!


With the key in the driver's door OR by pressing the central locking button in the middle console. They both do the same thing.

Yes I have resistance on the key when I try to unlock the door. There is no physical lever to lock the door, but there is a physical lever to unlock it if the actuator fails. The micro-switch on the tumbler assembly appears to be working because when I try and lock the doors from the driver's side, it's actuating the passenger door lock. The passenger door lock goes down briefly and then pops back up.

I was having problems with the passenger light sensor switch not working, so I pulled it out and the wire was loose on the end of the switch. I re-crimped it and checked the driver's side to make sure all was OK. Both light sensor switches are now working, but I still have locking problems.

By pressing the center console button, the passenger door will lock and then pop right back up and the driver's door does nothing. It doesn't even attempt to lock at all.

 

When you say there is no lever to lock the door, I'm not sure what you mean. I thought the key cylinder had a rod connected to it which goes down to the actuator. (Maybe not on the early years.) This allows you to lock/unlock the car with no power. As I understand it.

Anyway, the locks popping back up means that the alarm believes one of the doors is unlocked or it can't sense if the doors are locked. Since the drivers door isn't locking it sounds like this actuator may be your problem, but the system is working as it should when it unlocks the passenger door.

So, as I'm writing this (and my mine is thinking this through) this is what I believe is wrong. The drivers actuator motor isn't working or getting the power signal to lock and unlock. The actuator sensor is working which is why when you manually lock it (I think you said this) the passenger door locks. When you turn the key I am still surprised the door doesn't lock. But since the drivers door doesn't lock the alarm senses the locking failure and will always send an unlock signal which is why the passenger door unlocks.

Let you how your tests continue as the more information the better we can narrow this down. And, if you can get the car connected to a Hammer is will help you diagnose it. I don't remember what you said happens when you try locking the car from the center console button, but if the drivers doors doesn't lock when the button is hit is definitely sounds like the actuator motor or a wiring problem to the actuator motor.

Good luck.

 

Yes, the key cylinder does have an arm on it, but the locking mechanism only has one side on it where this arm can actuate it. Where it contacts the locking mechanism is in the unlocking direction key turn only and not in the locking direction.

I'm thinking it's also the actuator that is failing because it IS working part of the time and other times not depending on how hard the door is closed. I believe that the actuator has a failing contact in it and will probably have the local indy shop that has a Hammer hook it up and see what the code is.

 

OK, I've performed a bit of testing now that I have Adrian's book. I am by NO MEANS an electrical guy, so if you guys can give me a bit of help interpreting the results I'd appreciate it.

Using my volt meter, I found the ground pin (pin 5) and inserted the negative lead from the volt meter here. I then put the positive lead into pin 7 for the open position and as soon as I inserted the lead, I get 12 volts. When I turn the key in the driver's door to the "open the door" position, the voltage drops to 0. It says in the book that if you have an "earth ground", then the door actuator is bad.

Are my results what appears to be an "earth ground"?

Thanks guys,
Jim

 

Are you talking about the pins on the actuator? Most of the components in the locking system use a ground signal to perform their function. Especially at the controller box. It depends on where and what you are looking at when you see ground if the actuator is bad.

Tell me more details and what page in Adrian's book you're talking about.

 

Page 419 of Adrian's book and testing at the control unit's plug. Negative lead from the volt meter in pin 5 and the positive lead in pin 7 and then turning the key to the locked position. Initially plugging up both leads shows 12 volts and then when the key is turned in the driver's door lock to the locked position, it goes to 0 volts on the meter. Is this an "earth ground" that Adrian is speaking of?

 

Based on the diagram you are looking at you should see your voltage go to ground. When you turn the key, it grounds pin 7 which would send a signal (12 volts) on pin 3 which is what activates the actuators.

If you do the first thing Adrian has listed, which is grounds pin 3 and put 12 volts on pin 4 the doors should unlock, with the voltage and ground reversed on pins 3 and 4 the doors should lock. This is all done with the connector disconnected.

If you perform the tests listed in Adrian's book, the actuators should perform appropriately. If not, the actuators are a problem.

But, I would like to revisit something from before. You said something about when you slam the door hard, everything works and other times it doesn't. Can you provide more information on this?

 

Yes, a couple of weeks ago when this problem first started, I had a handful of things and let the door slam shut while the car was on an incline. It was then for the first time that it would not lock. I figured that it was the shock that the actuators take when the doors are closed that has caused it to become intermittent, but wanted to verify for sure before I spent the money to buy an actuator.

Not being an electrical guy, I can follow the instructions in Adrian's book, but wanted to know what he meant by "earth ground" and how to tell that it is grounding out while testing.

 

Earth ground is 0 volts or any piece of metal in the car. The car's body is a ground which is what he is discussing.

What intrigues me is, you say the lock works sometimes and it started when the door slammed extremely hard. I really wonder whether a wire is loose or something is misaligned mechanically somewhere stopping the actuator from moving.

Yes, it could be an intermittent problem with the actuator, but this other information causes me a little doubt.

 

I believe there is a dead spot in the track of the actuator after closing the door. I opened and closed the door until it failed to operate and then tested the circuit and it shows 0 volts when turning the key to the lock position. It doesn't take a really hard slam to make it fail, sometimes a normal closing causes the problem.

I've had the door handle and actuator out of the door making sure everything is in alignment as well as aligning the striker plate assembly so that the door closes easily like the passenger door does. I've also tried moving the actuator up and down in the track as far as the adjustors will let it adjust to no avail. It will work for 2 or 3 open/closes and then fail off and on.

 

What voltage does the circuit show with the actuator working and turning the key to the lock position?

 

I just happened to check the passenger side and it stays at 12V when turning the key.

 

This makes no sense to me, maybe I don't understand what you are doing.