For 1990-2009 cars

### Circuit Description

The body control module (BCM) provides a high side drive output through the headlamp washer relay control circuit that controls the headlamp washer relay.

### DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B3810 Headlamp Washer Relay Circuit

This vehicle has DTCs which include DTC Symptoms.

DTC Symptom | DTC Symptom Descriptor
--- | ---
02 | Short to ground
05 | Short to battery or open

### Conditions for Running the DTC

The only requirements are valid operating voltage and ground.

### Conditions for Setting the DTC

All of the following conditions exist for more than 1 second:

#### B3810 02

The BCM detects a short to ground in the headlamp washer relay control circuit when the output is active.

#### B3810 05

The BCM detects a short to battery voltage or an open in the headlamp washer relay control circuit when the output is inactive.

### Action Taken When the DTC Sets

#### B3810 02

The BCM disables the headlamp washer function.

### Conditions for Clearing the DTC

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

• | The 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.

1. During the headlamp washer fluid pump relay operation, listen for an audible click. Command the ON and the OFF states. Repeat the commands as necessary.

2. This step tests for constant voltage in the control circuit of the headlamp washer fluid pump relay.

3. This step verifies that the BCM is applying voltage through the control circuit to the headlamp washer fluid pump relay.

4. This step tests for an open in the ground circuit of the headlamp washer fluid pump relay.

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: Wiper/Washer Schematics Connector End View Reference: Component Connector End Views
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle
2 |

1. Turn OFF the ignition.
2. Install a scan tool.
3. Turn ON the ignition, with the engine OFF.
4. With a scan tool, navigate to the Headlamp Washer relay control parameter by making the following selections:

• | Wipers/Washer Systems

• | Special Functions

• | Body Control Module

• | Miscellaneous Tests

5. With the scan tool, command the Headlamp Washer relay ON and OFF.

Does the headlamp washer relay turn ON and OFF with each command?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3 |

1. Turn OFF the ignition.
2. Disconnect the wiper headlamp washer relay.
3. Turn ON the ignition, with the engine OFF.
4. Connect a test lamp from the control circuit of the headlamp washer relay to a good ground.

Does the test lamp illuminate?

Go to Step 7

Go to Step 4

4 | With the test lamp still connected to the control circuit of the headlamp washer relay, command the Headlamp Washer relay ON. Does the test lamp illuminate? | Go to Step 5 | Go to Step 6
5 |

1. Connect the test lamp between the control circuit of the headlamp washer relay and the ground circuit of the headlamp washer relay.
2. With a scan tool, command the Headlamp Washer relay ON.

Does the test lamp illuminate?

Go to Step 8

Go to Step 10

6 | Test the control circuit of the headlamp washer relay for a short to ground or an open. Refer to Circuit Testing and to Wiring Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 9
7 |

1. Turn ON the ignition, with the engine OFF.
2. Test the control circuit of the headlamp washer relay for a short to voltage. Refer to Circuit Testing and to Wiring Repairs .

Did you find and correct the condition?

Go to Step 13

Go to Step 9

8 | Inspect for poor connections at the headlamp washer relay. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 11
9 | Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 12
10 | Repair the open in the ground circuit of the headlamp washer relay. Refer to Wiring Repairs . Did you complete the repair? | Go to Step 13 | --
11 | Replace the headlamp washer relay. Did you complete the replacement? | Go to Step 13 | --
12 | Replace the BCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 13 | --
13 |

1. Use the scan tool in order to clear the DTCs.
2. Operate the vehicle within the Conditions for Running the DTC.

Does the DTC reset?

Go to Step 2

System OK