GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2006 🢒 XLR 🢒 DTC 🢒 DTC B3810

Circuit Description

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

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B3810 Headlamp Washer Relay Circuit

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 headlamp washer relay control when output is active.

B3810 05

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

Action Taken When the DTC Sets

B3810 02

The BCM disables the headlamp washer function.

Conditions for Clearing the DTC
    • A current DTC clears when the malfunction is no longer present.
    • A 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.

  2. Verifies that the BCM is providing voltage to the headlamp washer fluid pump relay.

    3.

  3. Tests for an open in the ground circuit to the headlamp washer fluid pump relay.

    4.

  4. Tests for constant voltage to the headlamp washer fluid pump relay.

    5.

  5. Test the headlamp washer fluid pump relay control circuit for a short to ground or open.

Step

Action

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

Go to Diagnostic System Check - Vehicle

2

  1. Turn ON the ignition, with the engine OFF.
  2. With a 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 headlamp washer relay.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp to ground.

    5. Probe the control circuit of the headlamp washer relay with the test lamp.

  5. With a scan tool, command the headlamp washer relay ON and OFF.

Does the test lamp turn ON and OFF with each command?

Go to Step 4

Go to Step 5

4

  1. Connect a test lamp across 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 and OFF.

Does the test lamp turn ON and OFF with each command?

Go to Step 8

Go to Step 10

5

Does the test lamp remain illuminated with each command?

Go to Step 7

Go to Step 6

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 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