TRUNK LOCK VACUUM SOLENOID
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TRUNK LOCK VACUUM SOLENOID
Hi everyone, quick question for my 1995 Audi 90 4 door sedan.
This winter, trying to unlock the trunk with the key something malfunctioned (broke) and:
If I try to lock or unlock the car from the trunk lock, it doesn't (only the trunk does).
If I lock and unlock the car from any of the front doors, the trunk gets locked or unlocked,
hence the vacuum system works.
Took the liner off from the trunk and looked at the hinges going from the blue vacuum solenoid to the trunk lock cylinder. Nothing broken all in good order. Took the cylinder apart, all seems ok.
Now, what's the problem logically? Is the trunk lock activating the solenoid to close and open all the car doors or is it the blue little pump? What am I to change here because I don't know.
If the car gets locked or unlocked from the doors, then the vacuum pumps are working AT THE DOORS. If I try the trunk, ONLY the trunk works not the rest of the car.
I don't know what actually activates the rest of the system? Is it the trunk lock cylinder or the trunk vacuum pump?
This winter, trying to unlock the trunk with the key something malfunctioned (broke) and:
If I try to lock or unlock the car from the trunk lock, it doesn't (only the trunk does).
If I lock and unlock the car from any of the front doors, the trunk gets locked or unlocked,
hence the vacuum system works.
Took the liner off from the trunk and looked at the hinges going from the blue vacuum solenoid to the trunk lock cylinder. Nothing broken all in good order. Took the cylinder apart, all seems ok.
Now, what's the problem logically? Is the trunk lock activating the solenoid to close and open all the car doors or is it the blue little pump? What am I to change here because I don't know.
If the car gets locked or unlocked from the doors, then the vacuum pumps are working AT THE DOORS. If I try the trunk, ONLY the trunk works not the rest of the car.
I don't know what actually activates the rest of the system? Is it the trunk lock cylinder or the trunk vacuum pump?
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From: Tucson, AZ
From what I remember the rear lock for the trunk has an electrical connection going to it. I'm not positive of the function for this connector, but I believe this is what actuates the central locking system.
Also, just because you didn't see any damage to the wires in the bundle in the trunk hinge, there is no guarantee there is not internal damage. The only way to know for sure is to ohm out the wiring.
Also, just because you didn't see any damage to the wires in the bundle in the trunk hinge, there is no guarantee there is not internal damage. The only way to know for sure is to ohm out the wiring.
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Yes it's a three wire connector. Is there an electric element in the key cylinder and is this one activating the pump or is the movement activating the pump and the electrical connector only there for the beep reminder and the overall electrical circuit security of the car?
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From: Scotia, NY
The wire at the hinge is 7 conductors.
It's a regular pinch and fail point.
The trunk lock itself has four wires going to it.
If it works from the door to lock/unlock all and not the trunk, then either one of the wires to the trunk are cut or one of the two micro-switches attached to the trunk lock are dead or disconnected.
It's a regular pinch and fail point.
The trunk lock itself has four wires going to it.
If it works from the door to lock/unlock all and not the trunk, then either one of the wires to the trunk are cut or one of the two micro-switches attached to the trunk lock are dead or disconnected.
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So if I understand correctly, the two black electrical units inside the trunk lock cylinder activate the blue vacuum pump and lock/unlock the whole car if the key is turned form the trunk lock.
Then, logically, if I manually push either of the rods connected to this cylinder and to the blue vacuum pump in the trunk, the car should lock or unlock, right? Wrong! It doesn't.
My question is simple, what SPECIFIC part form the trunk area locks and unlocks the whole car when the key is twisted from the back lock? Is it the lock, the pump, a combination of the two, anything else? I need to replace that part so that I can lock the car from the back lock once I empty my trunk without going to lock it from the doors.
Then, logically, if I manually push either of the rods connected to this cylinder and to the blue vacuum pump in the trunk, the car should lock or unlock, right? Wrong! It doesn't.
My question is simple, what SPECIFIC part form the trunk area locks and unlocks the whole car when the key is twisted from the back lock? Is it the lock, the pump, a combination of the two, anything else? I need to replace that part so that I can lock the car from the back lock once I empty my trunk without going to lock it from the doors.
AudiWorld Member
Joined: Apr 2005
Posts: 442
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From: Tucson, AZ
My question is simple, what SPECIFIC part form the trunk area locks and unlocks the whole car when the key is twisted from the back lock? Is it the lock, the pump, a combination of the two, anything else? I need to replace that part so that I can lock the car from the back lock once I empty my trunk without going to lock it from the doors.
Have you checked the wiring in the hinge area like everyone is telling you? If the wiring is 100% then you probably have a bad back lock.
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Hi,
all the wiring is ok. I have a bad lock then. I tried to swap the key cylinder element from mine to a 1993
audi 100 (they are identical) but when I looked properly the interior chrome metal tip (about 1 inch) which carries the black half moon plastic part connected to the rods, was snapped off. I need to get another one, seems like a very common defective unit like the antenna motor (got it from a mercedes if you can imagine). Until I find a good one on a car that year, it's gonna take a while and possibly not gonna work long either. Thank you much
all the wiring is ok. I have a bad lock then. I tried to swap the key cylinder element from mine to a 1993
audi 100 (they are identical) but when I looked properly the interior chrome metal tip (about 1 inch) which carries the black half moon plastic part connected to the rods, was snapped off. I need to get another one, seems like a very common defective unit like the antenna motor (got it from a mercedes if you can imagine). Until I find a good one on a car that year, it's gonna take a while and possibly not gonna work long either. Thank you much
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Joe Kucinski
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From: Scotia, NY
I've got a set of unknown from the old lock cylinder that was seized in my 1993, actually have the whole lock dis-assembled and I can let it all go cheaply, say, $10 plus shipping. I've no idea how it goes back together, so don't take yours apart until you get the replacement bits.
PM me if you want the lock and parts, the tumbler is dead but the external parts were still usable, I just ended up with a complete assembly to replace it.
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Guys, thank you much, I just got a new unit and I am trying to take apart mine but I better calm down because if there's something complicated, this is it. I think I need to replace the microswitches but I have no idea what and how they activate the mechanism inside. I had a diagram of a gentleman who replaced the lock cylinder unit but that's not what is wrong with mine. I remember the sound and the feel of the key that snapped something in the cylinder that cold day in the winter like it was today. I think something is broken between the microswitches and the lock cylinder itself. Don't know if this is a repairable part. What do you think?