Circuit Description
The rear wiper motor is supplied battery positive voltage and ground. The liftgate control module controls rear wiper motor operation through the rear wiper motor control circuit. The rear wiper motor control circuit is supplied a battery positive reference voltage by the rear wiper motor module and is pulse width modulated to ground by the liftgate control module. The duty cycle of the pulse width modulation (PWM) determines the rear wiper motor operating mode.
DTC Descriptors
This diagnostic procedure supports the following DTCs:
| • | DTC B1017 Output Driver Module Performance |
| • | DTC B3970 Rear Wiper Motor Circuit |
Conditions for Running the DTC
Battery voltage must be between 9-16 volts.
Conditions for Setting the DTC
The rear wiper motor control circuit is shorted to voltage.
Action Taken When the DTC Sets
The rear wiper/washer system will be disabled for as long as the DTC is current.
Conditions for Clearing the DTC
| • | The DTC will be current for as long as the fault is present and it will be latched for the respective ignition cycle. |
| • | A history DTC will be cleared after 100 error-free ignition cycles. |
Step | Action | Value(s) | 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 | |
2 |
Does the rear wiper motor operate normally? | -- | Go to Testing for Intermittent Conditions and Poor Connections | Go to Step 3 |
3 |
Does the test lamp illuminate? | -- | Go to Step 4 | Go to Step 8 |
4 | Connect a test lamp from the battery positive voltage supply circuit terminal to the ground circuit terminal in the rear wiper motor harness connector. Does the test lamp illuminate? | -- | Go to Step 5 | Go to Step 9 |
5 |
Is the voltage within the specified values? | 10-14 V | Go to Step 6 | Go to Step 7 |
6 | Test the rear wiper motor control circuit for high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 12 |
7 | Test the rear wiper motor control circuit for an open or short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 10 |
8 | Repair the battery positive voltage circuit to the rear wiper motor. Refer to Wiring Repairs . Did you complete the repair? | -- | Go to Step 14 | -- |
9 | Repair the rear wiper motor ground circuit for an open or high resistance. Refer to Wiring Repairs . Did you complete the repair? | -- | Go to Step 14 | -- |
10 | Inspect for poor connections at the harness connector of the rear wiper motor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 11 |
11 | Replace the rear wiper motor. Refer to Rear Window Wiper Motor Replacement . Did you complete the replacement? | -- | Go to Step 14 | -- |
12 | Inspect for poor connections at the harness connector of the LGM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 13 |
13 | Replace the LGM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 14 | -- |
14 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
