DTC 20: Operation Signal To Rear Window Defroster Switch On/Off Signal
WARNING: This page is about a different car, the 2002 Mazda MPV. However, it is still accessible from the selected car via links, so may be relevant.
Wait for 2 seconds after selecting DTC 20. If rear window defroster relay turns on and off 3 times, rear window defroster relay is okay. If rear window defroster relay does not turn on and off 3 times, remove instrument cluster. See INSTRUMENT CLUSTER under REMOVAL & INSTALLATION. Using a DVOM, measure voltage between instrument cluster connector No. 3, terminal 3P and ground. See Figure . If battery voltage is present, replace instrument cluster. If battery voltage is not present, check front climate control unit and wiring harness from battery to front climate control unit. See WIRING DIAGRAMS . Repair or replace as necessary. Retest system.