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Taillight Relay Circuit

  1. Remove wireless door lock ECU (leave wire harness connected). Using DVOM, measure voltage (backprobe) between ground and terminal No. 4 (Brown wire) at wireless door lock ECU harness connector. See Figure. Check for one short voltage signal as LOCK button is pressed on transmitter, and 2 short voltage signals as UNLOCK button is pressed on transmitter. If voltage signals are as specified, go to next step. If voltage signals are not as specified, replace wireless door lock ECU.
  2. Check for open in taillight relay circuit between wireless door lock ECU and taillight control relay. See WIRING DIAGRAMS . Repair as necessary.
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