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Test P

PINPOINT TEST P: THE DEFROST SYSTEM WILL NOT SHUT OFF AUTOMATICALLY - HEATED WIPER PARK


Test P1-P2:






Test P2-P3:






Test P3 Continued:






Normal Operation
The heated wiper park relay is powered by the auxiliary junction box (AJB) fuse 13 (30A) through circuit 30-HB8 (RD/OG). When the ambient temperature falls below 3°C (38°F), the module will ground circuit 91S-HB7 (BN/RD), closing the heated wiper park relay. This will allow power to flow through circuit 30S-HB42 (RD/YE) to the heated wiper park grids in the windshield. It will automatically switch off when the ambient temperature rises above 3°C (38°F).

Possible Causes
- circuit 91S-HB7 (BN/RD) shorted to ground
- circuit 30S-HB42 (RD/YE) shorted to voltage
- heated wiper park relay
- DATC module
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