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Ecu Power Source Circuit Test

Check DOME fuse (7.5-amp) in engine compartment junction block. Replace fuse if necessary and check wiring for short. Backprobe for voltage at wireless door lock ECU terminal No. 8 (Red wire). See Fig 1. If battery voltage exists, proceed to the next test listed in TROUBLE SHOOTING . If battery voltage does not exist, check for open in White/Black wire between vehicle ground and the wireless door lock ECU. See WIRING DIAGRAMS . Repair or replace circuit as necessary. If White/Black wire is okay, check circuit between wireless door lock ECU and battery. Repair or replace circuit as necessary and retest system operation.

Fig 1: Wireless Door Lock ECU Terminals (Component & Connector Views)
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