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For those of you with the power fold option, a neat little mod.

As per title, here are a couple of ways to interface the power fold mirrors with an alarm system so they retract and open with the door locks.

System 1 (ultimate system)

This system involves an extremely simple mod of the power fold ECU to give you SEPARATE control over the retract and open commands.

Because of this you can always be sure your mirrors will retract when locked and open when unlocked.

You need to open up the ECU located in the passenger door and solder a 1K resistor onto the 2 diodes as shown in the picture below then bring the wires through the door rubber into the dash where your alarm interfaces the door locks:

Power fold mod

If you now ground the UNFOLD wire the mirrors will open, if you ground the FOLD wire, the mirrors will retract.

To wire this into the alarm system you need to follow the simple diagram below and add a couple of diodes into the door lock circuit. These prevent the mirrors folding when the door locks are manually triggered.

The supra uses a GROUNDING pulse to trigger the door locks.

Power fold mirror alarm interface02

This system is pretty much the ultimate interface as, the trigger to open or close is dedicated so, the command will ALWAYS be the correct one & will only trigger the once.

System 2 (no modding ECU)

The following method interfaces the fold/unfold command in the stock wiring harness. You can use this system if you don't want to remove the door card or modify the mirror ECU.

Unlike the system above this system is not perfect - why? - Well, the factory trigger system runs off a single pulse to fold and unfold, this means if the mirrors are already retracted and you lock the car, the mirrors will unfold as, the pulse system simply toggles between the 2 positions where as the above system actually gives you individual control of the 2 parts of the circuit.

This is a POSITIVE trigger system which involves tapping into the ORANGE trigger wire from the mirror switch.

This can either be obtained at the mirror control switch connector or the passenger door connector behind the kick panel.

Power fold connector
Power fold connector 2

The control can be done through a relay as per the diagram below:

Power fold mirror alarm interface stock trigger

This system uses more diodes, one set prevents the mirrors triggering when the door locks are manually switched inside the car, the other set separate the lock & unlock commands from the alarm to control the relay.

Some alarm systems now have programable outputs which can be configured to change state , pulse, latch etc depending on what you desire.

If your alarm has such an output capable of delivering a positive pulse when the alarm is armed and disarmed, you can simply connect this directly to the orange command wire.


For those not in the know, diode orientation is below:

Diode orientation

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If you found this guide helpful or have a comment, please sign my Guest Book or use the Message Board.