B3715

DTC B3715

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC B3715 00
- Front Wiper Relay Drive Circuit

Diagnostic Fault Information






Circuit/System Description

The body control module (BCM) monitors the control circuit of the wiper relay. The voltage level should be low while the wiper relay is de-energized and near system voltage when the relay is energized. After the BCM receives a low, intermittent, or mist signal from the wiper/washer switch, it responds by applying battery voltage through the wiper relay control circuit to the coil side of the relay, energizing the WIPER relay.

Conditions for Running the DTC

This DTC can set only when the output is actively being requested by the BCM.

Conditions for Setting the DTC

If the BCM detects a short to ground in the wiper relay control circuit.

Action Taken When the DTC Sets

The BCM will not activate the output.

Conditions for Clearing the DTC

* The current DTC will become history when the request for the output is removed or when the condition for setting the fault is corrected.
* The history DTC will clear after 50 consecutive ignition cycles without a fault present.

Circuit/System Verification

Ignition ON, wiper switch in LOW position. Verify the windshield wipers are cycling at the low speed.

Circuit/System Testing

1. Ignition OFF, disconnect the WPR relay.
2. Connect a test lamp between the control circuit terminal 86 and ground.
3. Ignition ON, command the low speed wipers ON and OFF using the wiper switch. The test lamp should turn ON and OFF when changing between the commanded states.

^ If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.
^ If the test lamp is always OFF, test for a short to ground or an open/high resistance on the control circuit. If the circuit tests normal, replace the BCM.

4. If all circuits test normal, test or replace the WPR relay.

Component Testing

Relay Test
1. Ignition OFF, disconnect the WPR relay.
2. Test for 60-200 ohms between terminals 85 and 86.

^ If the resistance is not within the specified range, replace the relay.

3. Test for infinite resistance between the following terminals:

* 30 and 86
* 30 and 87
* 30 and 85
* 85 and 87

^ If not the specified value, replace the relay.

4. Test for less than 2 ohms between terminals 30 and 87A.

^ If greater than the specified range, replace the relay.

5. Install a 10A fused jumper wire between relay terminal 85 and 12 volts. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms between terminals 30 and 87.

^ If greater than the specified range, replace the relay.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests