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BLUF, I'm having minor issues with the alarm and door locks. The alarm is pretty well fixed I think, but the passenger door still doesn't lock or unlock with the driver's door, and hasn't for years.
For some background regarding the alarm, I was definitely not the first owner and I don't think my alarm has every worked properly. It had a viper alarm in it for years but I never used it, never had the key fobs for it, and I removed it several years ago and did a half *** repair job (just spliced with solderless connectors) on any wires that were damaged. In 2015 I took the car to Chris Ludwig for an ECU install and harness build and I noticed the alarm was setting itself after I got it back. No fault of Chris, I just was surprised that it was working, or kind of working. It was setting when the doors were closed, they didn't need to be locked. It made for some laughs when I'd set the alarm off by simply opening the doors, and it happened often at first, so there's that. Either way, I don't think Chris even messed with any of that wiring, so I'm not sure why it started working.
A couple weeks ago I heard the alarm setting while the passenger door was open, and then the alarm went off while the door was still open. I always assumed the alarm issues were due to CPU2, so I bought a new one a couple years ago and I finally installed it a couple days ago. The old CPU2 circuit board looked OK for the most part, from my limited knowledge on circuit boards and using a magnifying glass and light, but I did notice one of the caps (C3) looked like one of the legs was burned, although the cap itself looked OK. And the solder overall looked somewhat dull, so possibly cold solder.
When I was pulling out the old CPU2, I noticed a couple wires that were broken, 1I going to J4-08 (right hand door lock switch), so I guess that would explain why the alarm armed with the passenger door open. The other broken wire was 1N going to I3-08 and J4-05 (door key cylinder switches). So I soldered both of those along with two wires I spliced with solderless connectors before (1F and 1G). After installing the new CPU2, the alarm no longer arms with the doors closed but unlocked (WIN), but it only arms if locked from inside and then the door is closed. It will not arm using the key in the cylinder, but it will disarm that way (as it always has). So while it's working better, I feel like it's still not working 100% correctly.
Now, regarding the history behind the door locks, I disconnected J4-07 about 12 years ago because I had a draw on the battery and traced it to that connector. I didn't think much of it because it seemed like everything still worked normally. I noticed at some point that the passenger side no longer unlocked with the driver's side, but I figured that was due to the connector being disconnected. After I installed the new CPU2 I reconnected J4-07 with no change in function. I checked continuity between J4-07 and J4-01 and K2-01, and between J4-08 and J4-01 and K201, and the only place I don't get continuity is where the red line is. Everywhere there is a green line is good. So the G/R wire from J4-07 to either J4-01 or K2-01 has no continuity, but there is continuity between J4-01 and K2-01. I assume this is where my problem lies because I can't see why there would be any other factors causing this, but I thought I'd ask first. For the record, all of these connectors are disconnected from CPU2/door lock timer unit and other connectors when I tested this. I opened up the door lock timer unit and everything looks good in there too.
Any gurus out there have any input on this? Any common issues I don't know about?
I think the big thing you are up against is the old alarm install. Those installs in the 90's were BRUTAL on wiring. I've seen cars with the most bizarre problem from a crappy alarm install. God help you if the alarm also had remote start - you'd have a car starting itself in the middle of the night, not wanting to start, doors opening and closing on their own, you name it.
All that said, you may need to look into the door latches themselves. This is the part of the door that catches the U-shaped hook on the body to keep the door closed. It's not terrible to remove it but you do have to remove the glass and the rear window track.
The latch has microswitches for a few functions, such as door open and lock status. The door handles also have a switch, I think that's mainly the switch to turn on the keyhole light when you lift up on the handle.
You may want to get the Body Electrical Manual and look at the section on the alarm system, that will have more detail.
I'm wondering if the microswitches on the latches were bypassed or something. You may be able to test that without totally pulling the latch out, though, but it may be worth going that deep to see if anything was hacked on.
Also, the latch on the passenger side has the motor that locks and unlocks the passenger door. You put your key in the driver's door, you unlock it, the passenger door then mimics that action. Same for locking the driver door. There is no motor in the driver's side door, there are threads on adding a RHD motor to a driver door latch to add keyless entry.
TIL what...TIL stands for? lol And ditto what Pete said.
Originally Posted by DaleClark
I think the big thing you are up against is the old alarm install. Those installs in the 90's were BRUTAL on wiring. I've seen cars with the most bizarre problem from a crappy alarm install. God help you if the alarm also had remote start - you'd have a car starting itself in the middle of the night, not wanting to start, doors opening and closing on their own, you name it.
Yeah I might have to just pull that part of the harness from the door and unwrap it all. Honestly, this issue isn't a huge deal to me, but I'm reaching the point in my project that I'm interested in ironing out all the little things, and I figure while I have the door apart and it's winter, I might as well tackle this now. Luckily(?) this alarm install was old enough that I don't think remote start existed yet, or at least wasn't widely used. I think the only thing I haven't removed from that install is the actuator wiring from the door, and I think I've repaired any wiring that was funky, but I could be wrong.
Originally Posted by DaleClark
All that said, you may need to look into the door latches themselves. This is the part of the door that catches the U-shaped hook on the body to keep the door closed. It's not terrible to remove it but you do have to remove the glass and the rear window track.
The glass is out already anyway, so I imagine it won't be too much more to remove the rear track. Is that where the door key cylinder switches are (I3-08 and J4-05)? The name implies they're on the cylinders themselves, but I don't see anything that stands out as a switch, especially the shape they are shown to be in the FSM.
Originally Posted by DaleClark
You may want to get the Body Electrical Manual and look at the section on the alarm system, that will have more detail.
I thought that's where I got the screen grabs from, but that was from the 94 wiring diagram manual. I didn't realize the body electrical manual had so much more information in it, the whole troubleshooting procedure. Thanks!
Originally Posted by DaleClark
The latch has microswitches for a few functions, such as door open and lock status. The door handles also have a switch, I think that's mainly the switch to turn on the keyhole light when you lift up on the handle.
I'm wondering if the microswitches on the latches were bypassed or something. You may be able to test that without totally pulling the latch out, though, but it may be worth going that deep to see if anything was hacked on.
Yeah I'll pull the latches out if the troubleshooting steps don't work for me.
Originally Posted by DaleClark
Also, the latch on the passenger side has the motor that locks and unlocks the passenger door. You put your key in the driver's door, you unlock it, the passenger door then mimics that action. Same for locking the driver door. There is no motor in the driver's side door, there are threads on adding a RHD motor to a driver door latch to add keyless entry.
Dale
This did work at one point, but it was in the first few years of ownership.
The door handle does have a sensor that clips onto the back of the key cylinder. I think the idea there is when you turn the key that will register the key turn and the door latch registers an unlock which the security system sees as an OK unlock. If you use a slim Jim to pop the lock, the key cylinder sensor won't see that and the alarm will go off.
I think you can step through the BEM troubleshooting guide and find the root of the problem. Test each component.
The rear track for the Window is easy to remove with the glass out, just 2 10mm bolts. The rubber seal stays on the car, just remove the metal track. It's worth cleaning the rubber seal well and re-lubing it, I have a thread a while back on doing just that. If you're in that deep it's worth doing.
The door handle does have a sensor that clips onto the back of the key cylinder. I think the idea there is when you turn the key that will register the key turn and the door latch registers an unlock which the security system sees as an OK unlock. If you use a slim Jim to pop the lock, the key cylinder sensor won't see that and the alarm will go off.
I think you can step through the BEM troubleshooting guide and find the root of the problem. Test each component.
The rear track for the Window is easy to remove with the glass out, just 2 10mm bolts. The rubber seal stays on the car, just remove the metal track. It's worth cleaning the rubber seal well and re-lubing it, I have a thread a while back on doing just that. If you're in that deep it's worth doing.
Dale
Ah OK, good to know lol.
I never thought of what those two wires did. That makes sense. I always thought the sensor was in the latch or something.
Yeah I went through the troubleshooting steps tonight and discovered the fault is in the G/R wire between the door harness connector and the 3 way junction where the wire splits off to CPU2 and the timer box. The harness in the door checked out. The 3 way seems good. I'm wondering if it might be the connector itself. I didn't take the door off yet to access the connector. Maybe I'll remove the fender instead, that seems like it would be much easier to reinstall and line up properly.
I'm gonna skip removing the latch for the time being lol.
I finally got around to troubleshooting this again today. I wasn't excited about it because I thought I was going to have to remove the door or the fender, but I was able to get the connector poked through into the car. I had continuity from the connector to the 3-way, and since I'd already determined the door harness was good, that left me to inspecting the connectors themselves. They looked good, so I bent the pin upwards just a bit and it made contact and everything is working again.
Well, I should say the door lock system is fully functional again, but now the windows aren't working for some reason. I'm pretty sure all the connectors are connected, maybe I'm missing something. The windows aren't currently installed, but I don't see why that would be an issue.
12-05-21, 09:05 PM
