For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptors

DTC B3715 02: Front Wiper Relay Drive Circuit Short to Ground
DTC B3715 05: Front Wiper Relay Drive Circuit Short to Battery or Open

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Ignition 1 Voltage | 1 | 1 | -- | --
Windshield Wiper Motor Park Switch Signal | 1 | 1 | -- | --
Windshield Wiper Switch High Signal | 1 | 3 | B3715 05 | --
Windshield Wiper Switch Low/Pulse Signal | B3715 05 | 2 | 5 | --
Windshield Wiper Motor Relay Control | B3715 02 | B3715 05 | B3715 05 | --
Wiper Diode | -- | -- | -- | 6
Windshield Washer Switch Signal | 1 | 7 | 8 | --
Windshield Washer Pump Control | 1 | 7 | 8 | --
Windshield Wiper Motor High Speed Control | 1 | 3 | -- | --
Windshield Wiper Motor Low Speed Control | 1 | 2 | -- | --
Windshield Wiper Motor Park Switch Signal | 2, 4 | 2, 4 | -- | --
Windshield Washer Pump Ground | -- | 7 | -- | --
Windshield Wiper Motor Ground | -- | 1 | -- | --
Wiper ON/OFF Relay Ground | -- | B3715 05 | -- | --
1. Wipers and washers inoperative all modes 2. Delay or low speed wipers inoperative 3. High speed wipers inoperative 4. Wipers do not park 5. Wipers always on

6. Wipers operate at high speed in the low speed mode

7. Washers inoperative

8. Washers always on

### Circuit/System Description

The body control module (BCM) monitors the voltage level on the windshield wiper motor relay coil supply voltage circuit that controls the WPR 70 On/Off relay. The voltage level on this circuit should be low while the wiper system is off and the relay is de-energized. The voltage will be near system voltage when the relay is energized. After the BCM receives a low, delay, or mist signal from the wiper/washer switch, it responds by applying battery voltage to the wiper motor relay coil supply voltage circuit energizing the WPR 70 On/Off relay.

### Conditions for Running the DTC

Ignition ON.

### Conditions for Setting the DTC

The following conditions exist for more than 1 second:

#### B3715 02

The BCM detects a short to ground in the windshield wiper relay coil control circuit when the output is active.

#### B3715 05

The BCM detects a short to battery or an open in the windshield wiper relay coil control circuit when the output is inactive.

### Action Taken When the DTC Sets

The BCM disables the windshield wiper function.

### Conditions for Clearing the DTC

• | The current DTC clears when the malfunction is no longer present.

• | The history DTC will clear after 100 consecutive fault-free ignition cycles have occurred.

### Reference Information

#### Schematic Reference

Wiper/Washer Schematics

#### Connector End View Reference

Wiper/Washer Connector End Views

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

• | Scan Tool Output Controls

• | Scan Tool Data List

• | Scan Tool Data Definitions

### Circuit/System Testing

1. Ignition OFF, remove the WPR 70 On/Off relay.
2. Test for less than 5 ohms of resistance between the ground circuit terminal 85 and ground.

⇒ | If greater than 5 ohms, test the ground circuit for an open/high resistance.

3. Ignition OFF, remove the WPR 52 high speed relay.
4. Ignition ON, test for 0 volt between the wiper switch high signal circuit terminal 86 and ground.

⇒ | If greater than 0 volt, test the signal circuit for a short to voltage. If the circuit tests normal, replace the wiper/washer switch.

5. Ignition ON, connect a test lamp between the WPR 70 On/Off relay control circuit terminal 86 and ground.
6. Momentarily activate the wipers to the MIST position. The test lamp should momentarily turn ON and OFF.

⇒ | If the test lamp is always ON, test the relay control circuit for a short to voltage. If the circuit tests normal, replace the body control module.

⇒ | If the test lamp does not illuminate, test the relay control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the body control module.

7. Ignition OFF, disconnect the C2 harness connector at the body control module.
8. Wiper switch OFF, test for infinite resistance between the signal circuit terminal 57 and ground.

⇒ | If less than infinite resistance, test the signal circuit for a short to ground.

9. If all circuits test normal, replace the WPR 70 On/Off relay.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Relay Replacement

• | Windshield Wiper and Washer Switch Replacement

• | Control Module References for BCM replacement, setup, and programming