Need door lock schematic for 92 C4
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Joined: Aug 2007
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From: Austin TX
Need door lock schematic for 92 C4
Could someone kindly post the door lock schematic for a 92 C4. I am working on installing a Keyless Entry system, while retaining the factory Theft Deterrent System.
Last edited by mixalive; Aug 24, 2013 at 02:48 AM.
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Joined: Aug 2007
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From: Austin TX
Looking at the schematic, I am a little confused about one point.
Talking about the operation of the factory Theft Deterrent System: The 92 C4 does not come with a Keyless Entry System. The only way to deactivate the Theft Deterrent System (as per the manual) is to unlock the door with the key or insert the key into the ignition. The Theft Deterrent System will not deactivate by unlocking the door with the power door lock. So I would suspect there is a circuit activated by the door lock cylinders to notify the Theft Deterrent System to disarm. Anyone with some knowledge on this point? As this would be the circuit I would need to connect to the open button of a Keyless Entry System.
Talking about the operation of the factory Theft Deterrent System: The 92 C4 does not come with a Keyless Entry System. The only way to deactivate the Theft Deterrent System (as per the manual) is to unlock the door with the key or insert the key into the ignition. The Theft Deterrent System will not deactivate by unlocking the door with the power door lock. So I would suspect there is a circuit activated by the door lock cylinders to notify the Theft Deterrent System to disarm. Anyone with some knowledge on this point? As this would be the circuit I would need to connect to the open button of a Keyless Entry System.
Last edited by mixalive; Aug 24, 2013 at 02:53 AM.
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According to the electrical schematic and the text description in the FSM, the CCM is notified of an "open" position by the door lock motor. Beyond that, I don't see anything else in the FSM that further explains it, but I'm no expert.
Melting Slicks
Joined: Aug 1999
Posts: 2,240
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From: Baltimore, MD USA
On the back of the key cylinder for each door is a mechanical
switch with two wires. A Black/White wire which is ground and
a Light Green wire which goes to the CCM to disarm the alarm.
The Light Green wire is grounded when the key cylinder is turned
to the unlock position.
The Light Green wire can be accessed at the kick panel where
the wire comes thru the A pillar. Note: If you're doing this on the
driver side, there is another Light Green wire used for the Power
Mirror. You can tell if you have the correct wire by using an
ohm meter. The correct wire will be grounded when you turn
the key cylinder to the unlock position.
Your keyless entry needs to send a negative going signal to the
Light Green wire to disarm the factory alarm. It needs to send this
pulse before it sends the door unlock signal to the power door lock
acutators.
If it doesn't the factory alarm will think some one is unlocking the door and
the horn will start honking.
Your kit may have an option to increase the negative going pulse
width time or you can increase the time length of the pulse by using a
mechanical relay. This will work but you may hear the horn sound for a
split second.
switch with two wires. A Black/White wire which is ground and
a Light Green wire which goes to the CCM to disarm the alarm.
The Light Green wire is grounded when the key cylinder is turned
to the unlock position.
The Light Green wire can be accessed at the kick panel where
the wire comes thru the A pillar. Note: If you're doing this on the
driver side, there is another Light Green wire used for the Power
Mirror. You can tell if you have the correct wire by using an
ohm meter. The correct wire will be grounded when you turn
the key cylinder to the unlock position.
Your keyless entry needs to send a negative going signal to the
Light Green wire to disarm the factory alarm. It needs to send this
pulse before it sends the door unlock signal to the power door lock
acutators.
If it doesn't the factory alarm will think some one is unlocking the door and
the horn will start honking.
Your kit may have an option to increase the negative going pulse
width time or you can increase the time length of the pulse by using a
mechanical relay. This will work but you may hear the horn sound for a
split second.
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Thread Starter
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Joined: Aug 2007
Posts: 668
Likes: 38
From: Austin TX
Thanks.
I have all the schematics modified to accommodate the aftermarket keyless entry system, utilizing the components and integrity of the factory alarm, adding park lights flashing (triggered by the horn). After I do the install, and work out the bugs, I will post a how-to on the forum.
I have all the schematics modified to accommodate the aftermarket keyless entry system, utilizing the components and integrity of the factory alarm, adding park lights flashing (triggered by the horn). After I do the install, and work out the bugs, I will post a how-to on the forum.