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Complete TC Wiring Diagram

41624 Views 8 Replies 7 Participants Last post by  Savedbygrace
Radio Wiring Diagram:

For adding on line out converters (for amps on factory radios), hardwiring radar detectors or satellite radios, rewiring a headunit, etc.

12V Constant - blue
Ground - brown
Ignition - gray
Illumination - green
Power Antenna - orange
LF Speaker (+) - pink, (-) - purple
RF Speaker (+) - light green, (-) - blue
LR Speaker (+) - brown, (-) - yellow
RR Speaker (+) - red, (-) - white

Wiring Diagram for Alarms/ Remote Starts:

For installing an alarm, keyless entry, remote starter or hardwiring miscellaneous things.

12V Constant - red or white (ignition harness)
Starter - black (ignition harness)
Second Starter - green (ignition harness)
Ignition - blue (ignition harness)
Second Ignition - yellow (ignition harness)
Power Lock - green to blue (driver's kick panel, 20 pin plug) (use a mutlimeter to test this wire with the driver's door key cyliner)
Power Unlock - purple to pink (driver's kick panel, 20 pin plug) (double pulse, use a mutlimeter to test this wire with the driver's door key cyliner)
Parking Lights (+) - brown (top of fuse box, 30 pin plug)
Parking Lights (-) - brown (headlight switch)
Door Trigger (-) - orange (driver) and blue (passenger) (top of fuse box for both wires, diode isolate each)
Domelight Supervision - blue (left side of fuse box)
Trunk Trigger - purple (top of fuse box)
Trunk Release - orange (driver's kick, panel gray 12 pin plug)
Brake Wire - blue (brake pedal switch)
Parking Brake Wire - black (parking brake switch)
Tachometer - black (data link plug, or at the top plug of the ECM)

I'm a car technician at an auto shop so if u have ne questions about installs or wiring anything up, let me know n i'll be glad to help u out.
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I have a question, I have a 2009 scion tc nothing has been altered at all, ok. About 2 1/2 weeks ago I was inside the store and came out to a fire in my car between the driver seat and the e brake, the keys were in my pocket so no power was on anywhere, there is a 10 gage wire right there that we are trying to figure out what it went to. There is no coating on it so don't know what the color is. Any suggestions as to why? I attached two pictures of the damage.
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