B370B

DTC B370B

Diagnostic Instructions

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

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

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC B370B 04
- Rear Wiper Function Control Circuit Open/High Resistance

DTC B370B 02
- Rear Wiper Function Control Circuit Short to Ground

DTC B370B 01
- Rear Wiper Function Control Circuit Short to Voltage

Diagnostic Fault Information






Circuit/System Description

The body control module (BCM) controls the single speed rear wiper motor by its active high output to the external rear wiper motor relay. When the BCM activates its output and applies battery to the coil of the relay, the relay energizes, allowing battery voltage from the fuse to be applied through the switched contacts of the rear wiper motor relay to the control input of the rear wiper motor. The motor then operates continuously at low speed.

Conditions for Running the DTC

* Ignition ON

* The system voltage is between 9-16 V.

Conditions for Setting the DTC

A short to ground or an open/high resistance is detected in the rear window wiper control circuit.

Action Taken When the DTC Sets

Rear wiper operation is suspended.

Conditions for Clearing the DTC

A current DTC clears when the diagnostic runs and passes.

Reference Information

Schematic Reference

Wiper/Washer Schematics Electrical Diagrams

Connector End View Reference

Component Connector End Views Sunshade - Left Front

Description and Operation

Wiper/Washer System Description and Operation Description and Operation

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Control Module References for scan tool information

Circuit/System Testing

1. Ignition OFF and all vehicle systems OFF, disconnect the X2 harness connector at the X50A underhood fuse block. It may take up to 2 minutes for all vehicle systems to power down.

2. Test for less than 10 ohms between the rear wiper relay ground circuit terminal B5 and ground.

• If greater than 10 ohms

1. Test for less than 2 ohms in the ground circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.

• If less than 2 ohms, repair the open/high resistance in the ground connection.

3. Ignition ON.

4. Connect a test lamp between rear relay control circuit terminal C5 and ground.

5. Verify the test lamp turns ON and OFF when commanding the rear wipers ON and OFF with a scan tool.

• If the test lamp is always OFF

1. Ignition OFF, disconnect the X4 harness connector at the K9 body control module.

2. Test for infinite resistance between the control circuit and ground.

• If less than infinite resistance, repair the open/high resistance in the circuit.

• If infinite resistance

3. Test for less than 2 ohms in the control circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.

• If less than 2 ohms, replace the K9 body control module.

• If the test lamp is always ON

1. Ignition OFF, disconnect the X4 harness connector at the K9 body control module, ignition ON.

2. Test for less than 1 V between the control circuit and ground.

• If greater than 1 V, repair the short to voltage on the circuit.

• If less than 1 V, replace the K9 body control module.

• If test lamp turns ON and OFF

6. Test or replace the X50A underhood fuse block.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

* Rear Window Wiper Motor Replacement (Equinox) Rear Window Wiper Motor Replacement (Equinox)Rear Window Wiper Motor Replacement (Terrain) Rear Window Wiper Motor Replacement (Terrain)

* Control Module References Control Module References for BCM replacement, programming and setup