Circuit Description
The body control module (BCM) monitors the wiper relay control circuit of the wiper 1 relay. The voltage level should be low while the wiper relay is de-energized. The voltage will be near system voltage while the relay is energized. When the wiper switch is in Low, Intermittent, or Mist positions voltage from the windshield wiper washer switch is applied to the windshield wiper switch signal 1 input of the BCM. The BCM responds by switching control circuit of the wiper 1 relay to B+. This action energizes the wiper 1 relay, providing low speed operation.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B3715 Front Wiper Relay Drive Circuit
Conditions for Running the DTC
The ignition is in the RUN or ACC position.
Conditions for Setting the DTCs
The following conditions will cause the DTC to set:
| • | The BCM detects a short to ground. |
| • | The BCM detects a short to battery voltage. |
| • | The BCM detects an open circuit. |
Action Taken When the DTC Sets
| • | The windshield wipers will be disabled until the conditions mentioned above are no longer present for an open or short to battery. |
| • | The wipers will always be ON if the control circuit from the BCM to wiper relay 1 is shorted to B+. |
| • | No indicator will illuminate on the instrument panel (I/P). |
Conditions for Clearing the DTC
| • | A current DTC clears when the malfunction is no longer present. |
| • | A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step tests the ground at the coil side of the wiper 1 relay. The BCM supplies B+ to the coil side of the rear window defogger relay.
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This step tests the control circuit side of the wiper 1 relay for faults that caused the DTC B3715.
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This step tests the output of the BCM. Command both the ON and OFF states. Repeat the commands as necessary.
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After replacement of the BCM, you must calibrate the new module for proper operation.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Wiper/Washer Schematics Connector End View Reference: Wiper/Washer Connector End Views | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
Does the test lamp illuminate? | Go to Step 3 | Go to Step 8 | |
Did you find and correct the condition? | Go to Step 11 | Go to Step 4 | |
Does the test lamp turn ON and OFF? | Go to Step 6 | Go to Step 5 | |
5 | Test the control circuit of the wiper 1 relay for an open. Refer to Circuit Testing . Did you find and correct the condition? | Go to Step 11 | Go to Step 7 |
6 | Inspect for poor connections and terminal damage at the relay socket. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 11 | Go to Step 9 |
7 | Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 11 | Go to Step 10 |
8 | Repair the ground side of the control circuit of the wiper 1 relay. Refer to Wiring Repairs . Did you complete the repair? | Go to Step 11 | -- |
9 | Replace the wiper 1 relay. Did you complete the replacement? | Go to Step 11 | -- |
Replace the BCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 11 | -- | |
11 |
Does the DTC reset? | Go to Step 2 | System OK |
