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How to Repair

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Cadillac Repair Sloppy Ride

Installing an aftermarket remote control system 
for the power locks
By Stefan Knappe

My car was not factory equipped with a power lock remote control, so I decided to fit an aftermarket system.
Here's how I installed it in my car.
First I searched for an ideal location to physically install the module, which had the dimensions of a pack of cigarettes.
My choice was the panel in front of the trunk, to the rear of the back seat. Reason:
- easily accessible
- space available
- near most electrical connecting points

Remove all carpeting from the trunk, to do so, pull out the front panel first, then carefully remove the fasteners and spare wheel and lift out the carpet.

I fabricated a bracket, on which the module was fixed. This bracket was attached to an empty space on the aforementioned panel. Mounting points with inserted nuts were provided for other optional electrical components.

It is advisable to remove the negative battery cable when doing electrical installations.

Choose power sources from rear fuse box, one constant and one switched ignition.
Check that you connect to wires after the fuse, so that your wiring is protected.
Run these power wires to the remote module through the thick plastic cable channel on the upper left side of the trunk.

The factory power lock system is initiated by positive impulse. My choice was to connect directly to the power lock relay, which is on the same panel. Look for a light blue (lock) and a black (unlock) wire (pin A and F at connector). Connect the remote module in a way, that positive impulse is supplied to either of these connections when locking  or unlocking.

If you want to trigger the trunk opener, connect to the sending wire which is located in the thick round plastic cable channel running along the upper left side of the trunk.
Look for a rather thick black wire, which seperates from the main channnel where it enters the trunk lid at the left hinge. If in doubt, check with test light. Positive 12 Volts will actuate the solenoid.

If you want to indicate operation of the remote by turn signals flashing, connect the relevant output lines of the remote module with the dark green and yellow cables running to the rear light cluster, these operate the flashers. Either connect at the rear lamp cluster or in the aforementioned thick cable channel.
(Note: dark green = right   yellow = left)

To connect to the front flashers, run two cables to the dashboard. Remove rear bench, plastic cover along door sill, left kick panel and lower sound insulator. Connect to light blue / dark blue wires under steering column. Make sure to connect rear left to front left, and rear right to front right, otherwise you'll mess up flasher operation.
(Note: dark blue = right   light blue = left)
I separated front and rear flashers with diodes, refer to figure "A". These diodes should be able to handle current of about 2 amps.

I decided that I want to have the interior lights on when opening the car with the remote. To do so, I connected to the door handle input at the RAPIE* module, located at the right electronic panel. Connector A7 (grey) is grounded when you lift the door handle. As positive impulse is used to trigger the power locks, I installed an additional relay which provides ground (= negative) impulse to the RAPIE module.
This relay is a standard relay available in every auto parts store. For wiring schematics, refer to figure "B".

Another feature of most aftermarket remote units is an automatic lock function, which takes places if the car is unlocked by remote and no door is opened within 60 seconds. You need a door switch input to the remote.
There is one available at the left hand micro relay box (thin cable, grey/black, ground with door open), but it also gets ground when the interior lights are on, which happens when you unlock by remote. So it's not of use. I stopped at this point, and deactivated the auto-lock function at the module. I have some ideas how to get it working, but ran out of time for now. I will write it down when I have a practical solution.

Refer to below pictures for component locations.

Please keep in mind that these instruction are based upon my experience. I cannot be made responsible if something brakes on your car when you follow these instructions. Especially cable colours vary sometimes, so be careful. If in doubt, check circuits with a test light, or a high-impedance voltmeter on electronic components. You should have some experience working on car electrics.

The whole installation took about six hours.
 

* RAPIE = Retained Accessory Power / Illuminated Entry

  Figure A

Figure B
 
Component locations