Adding rear hatch to lock system
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Adding rear hatch to lock system
It bothers me that when I unlock the hatch I also have to later unlock the doors. Simply adding the hatch to the circuit would be bad since of course we don't want to pop the hatch everytime a door is unlocked. However, I have to believe one can add a switch to allow the front doors to unlock when the key is turned at the hatch? Hmmm?
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From: Cape Town
Heinrich
Not sure about this but I think on '90 and later cars one could operate the doors from the hatch lock by holding the key for a few seconds in it's turned position. Might be a simple(ish) relay mod. Can anybody confirm?
Colin
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Not sure about this but I think on '90 and later cars one could operate the doors from the hatch lock by holding the key for a few seconds in it's turned position. Might be a simple(ish) relay mod. Can anybody confirm?
Colin
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HMMM .the only switch and wires on the hatch lock turn on and off the alarm. So how to use the "off" wires to trigger the central locking button yet not interfere with the alarm ?? No answer here! But I am sure it involves a RELAY
Coling thanks for the tip 
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From: Boulder Creek, CA
Heinrich,
It looks like the hatch is already on a different circuit. I looked at 87 & 89 wiring diagrams and it looks like you could maybe just tie in the key-position switch on the hatch to the ones on the doors. I'm not sure what year car you're referring to, so double-check the correct wiring diagram.
If you think about it, it makes sense that they would separate them...
Use case: run out and put a couple of bags of groceries in the rear of the car, then walk off to another store.
It makes sense that the hatch switch will not unlock the doors, because the average person will most likely open the hatch, put the stuff in the car, close the hatch and walk off without thinking to stick the key back in the hatch and turn the key to arm the alarm (and lock the doors). I think they deliberately set it up so you have to explicitly unlock the doors... so you don't accidentally walk off with your car unlocked. In any case, the electric latch on the rear lid is not activated by any lock cylinders, it has it's own interlocked switch. You could probably jumper the hatch switch into the other circuit and get the result you want.
It looks like the hatch is already on a different circuit. I looked at 87 & 89 wiring diagrams and it looks like you could maybe just tie in the key-position switch on the hatch to the ones on the doors. I'm not sure what year car you're referring to, so double-check the correct wiring diagram.
If you think about it, it makes sense that they would separate them...
Use case: run out and put a couple of bags of groceries in the rear of the car, then walk off to another store.
It makes sense that the hatch switch will not unlock the doors, because the average person will most likely open the hatch, put the stuff in the car, close the hatch and walk off without thinking to stick the key back in the hatch and turn the key to arm the alarm (and lock the doors). I think they deliberately set it up so you have to explicitly unlock the doors... so you don't accidentally walk off with your car unlocked. In any case, the electric latch on the rear lid is not activated by any lock cylinders, it has it's own interlocked switch. You could probably jumper the hatch switch into the other circuit and get the result you want.
