okay, this is one weird situation.

The rear hatch lock started acting up about two months back, just after I had the wring harnesses replaced by the shop. It would unlock but not lock. May have been happening for months, I don't check that the hatch is locked after I errr, lock it.

I figured that I would look at it when the rains stopped. Then about a month ago the left rear door lock joined the party. unlocks fine with driver lock, but won't lock. Twitches a bit when I lock the driver's door, but doesn't lock down. Fine, still waiting for the rains to stop...

Yesterday weird stepped it up a notch.

1)
When I lock or unlock the drivers door none of the other doors lock or unlock. no twitching, no sound, nothing.

2)
The dome light (which is set to go on/off with door opening) didn't go on when i opened the door.

3)
When i switched the dome light to always on to see if the bulb was dead, the key-in with door-open alert starts pinging. Stops when the dome light is in off or follow door settings. Dome light did not go on. Visually it looks fine, and with no bulb the switch in "always on" did not trigger the pinging.

4)
If i pull up and hold the driver's door lock, or push down and hold, the key-in with door-open starts pinging.

Of course if the key is out of the ignition i don't get the pinging with door locks or dome lights, but that makes sense, the key is out :)


At this point a lesser man would claim possession.

OK, here's my stall: What harnesses did you have replaced? I could assume hatch left and right, but that would ruin my stall. Also, what year wiring diagram should I be referring to? Any other work coincident to the onset of these symptoms?
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Art Benstein near Baltimore

All the trouble I've ever been in started out as fun.....

Thanks Art.

this is a 1990 wagon - meant to mention that, sorry.

I had both hatch harnesses done, they used OEM harnesses. I haven't had any other work done since the steering rack over a year ago.

right hand side (1985-1993) volvo part # 1348019
left hand side (1986-1993) volvo part # 3544695

I don't know if the hatch lock-but-don't-unlock coincides with the harness replacement, i just know that soon after that I opened it up with a purchase and realized - hey, that should have been locked...

OK. I've stalled long enough. Let's try something easy.

Either measure the voltage on fuse 8's terminal like in the photo, or even easier, open the glove box and observe the light inside while operating the door locks. I'm hoping you'll just need to clean up that fuse and all will be well again. It works as an explanation for your symptoms, especially with the rain, but it isn't the only possibility.


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Art Benstein near Baltimore

If you tell the truth, you don't have to remember anything.

well that was weird....

took a look at the glove box. no light, but the pinging started when i opened it up ...

fuse 8 was blown wide open. replaced it and all the weird issues went away. left rear and hatch still don't autolock, but at least they try, and the other do so again.

fuse 8 also runs the radio, i don't usually have the radio front installed as this car is mainly a 7 minute commuter to the car park, but on Monday I took it into work and had the radio going.

If the fuse holds for the next few days, i'll try the radio again and see if that has the short. or, it could have been an old fuse.

So a reasonable explanation and solution, but i'm still rubbing down the wagon with garlic over the weekend.

OK, so you're back to the way it was when you got it back from the mechanic.

If in your place, I would disconnect both harness plugs for the tailgate, and then try the rear door lock, suspecting there may be a pinched wire lurking in the tailgate repair. It could also be a sluggish motor (gear mechanism) in the rear door's lock actuator -- they do leak and take on water sometimes, but I always jump to the last thing done as a good place to start looking for trouble.

Next, I would use an ammeter to make sure nothing on fuse 8 (which is hot all the time) is draining the battery, or your short trip home from the commuter lot may not occur until triple-A gives you a jump start.
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Art Benstein near Baltimore

If you think dogs can't count, try putting three dog biscuits in your pocket and then give him only two of them.
-Phil Pastoret

i can give that a check when i get to the car park tonight. would be a thrill if that was the easy solution.

A friend also suggested looked for old/cracked/exposed wiring in the harness in the driver's door wring boot.

Still keeping that priest on speed dial though...