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B3723

B3723 - Rear Wiper Relay Drive Circuit High

Schematic:




CIRCUIT DESCRIPTION
When operation of the rear wiper is selected, battery voltage from the rear wiper switch is applied to the rear wiper input of the body control module (BCM) circuit 94. The BCM responds by switching circuit 2445 to ground. This action energizes the rear wiper relay, providing power to the rear wiper motor.

DTC PARAMETERS
^ Ignition is in RUN or ACC position
^ Circuit 2445 shorted to battery voltage
^ Output is On
^ Service (wrench) light will illuminate

DIAGNOSTIC AIDS
^ When a shorted-to-battery voltage condition exists in circuit 2445 and the ECM has been requested to activate the rear wiper relay, the BCM will attempt to switch circuit 2445 to ground. High current flow will result and the BCM output will go into a protective state. The BCM output will not allow itself to be activated for as much as 3 minutes.
^ Check for poor connection at the BCM. Inspect harness connectors for backed out terminals, improper terminal mating, broken connector locks, improperly formed or damaged terminals and poor terminal-to-wire connection (terminal crimped over wire insulation and not conductors).
^ Inspect wiring harness for damage. Check for broken or chaffed insulation.
^ Review all fail information as this may assist in determining the conditions when the fault occurs.
^ If fault is suspected to be intermittent, wiggling harness wiring may help in locating fault.
^ The rear wipers are inoperative.

TEST

Diagnostic Chart: