GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Saturn 🢒 2006 🢒 VUE - AWD 🢒 DTC 🢒 DTC B3722

Circuit Description

When operation of the rear wiper is selected, battery voltage from the rear wiper switch is applied to the rear wiper switch signal input of the body control module (BCM) circuit. The BCM responds by switching the rear wiper relay control circuit to ground. This action energizes the rear wiper relay, providing power to the rear wiper motor.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B3722 Rear Wiper Relay Drive Circuit Low

Conditions for Running the DTC

The ignition is in RUN or ACC position.

Conditions for Setting the DTC
    • The rear wiper relay control circuit is shorted to ground or open.
    • The accessory voltage circuit to the coil side of the relay is open .
    • The accessory voltage circuit is shorted to ground between the fuse and the rear wiper motor.
    • The rear window wiper motor control circuit is shorted to ground.
    • The RR WIPER 15-amp fuse is open.

Actions Taken When the DTC Sets

Service (wrench) light will illuminate.

Conditions for Clearing the DTC
    • A current DTC clears when the fault is no longer present.
    • A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the fault.

Diagnostic Aids
    • Inspect for poor connection at the BCM. Inspect harness connectors for backed out terminals, improper terminal mating, broken connector locks, improperly formed or damaged terminals and poor terminal-to-wire connection, terminal crimped over wire insulation and not conductors.
    • If the rear wiper relay control circuit is open, the rear wipers will be inoperative.
    • If the rear wiper relay control circuit is shorted to ground, the rear wipers will always be ON.
    • If, either the accessory voltage circuit, or the rear window wiper motor control circuit is shorted to ground, the RR WIPER fuse will open and the rear wipers will be inoperative.
    • Inspect the wiring harness for damage. Inspect for broken or chaffed insulation.
    • If the fault is suspected to be intermittent, wiggling the harness wiring may help in locating fault.

Step

Action

Yes

No

Schematic Reference: Wiper/Washer Schematics

Connector End View Reference: Master Electrical Component List

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. Remove the rear wiper relay from the underhood fuse block (UHFB).
  3. Turn ON the ignition, with the engine OFF.
  4. Turn the rear wipers ON.
  5. With a test lamp connected to a good ground, probe the coil side accessory voltage supply circuit of the relay.
  6. With the test lamp still connected to a good ground, probe the switch side accessory voltage supply circuit of the relay.

Does the test lamp illuminate for both accessory voltage circuits?

Go to Step 3

Go to Step 4

3
  1. Connect the test lamp between the accessory voltage supply circuit and the rear wiper relay control circuit of the relay.
  2. Using a scan tool, command the rear wipers ON and OFF.

Does the test lamp illuminate when you command ON and go out when you command OFF?

Go to Step 8

Go to Step 7

4

Inspect for an open RR WIPER 15-amp fuse.

Is the fuse open?

Go to Step 5

Go to Step 11

5
  1. Turn OFF the ignition.
  2. Install the rear wiper relay.
  3. Replace the RR WIPER fuse with a new one.
  4. Turn ON the ignition with the engine OFF.
  5. Attempt to operate the rear wipers.

Does the RR WIPER fuse open again?

Go to Step 6

Go to Step 15

6

Test the following circuits of the rear wiper motor for a short to ground:

    • Accessory voltage circuit
    • Rear window wiper motor control circuit

Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 15

Go to Step 10

7

Test the rear wiper relay control circuit for an open or a short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 15

Go to Step 9

8

Inspect for poor connections and terminal damage at the UHFB. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 15

Go to Step 14

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 Connector Repairs .

Did you find and correct the condition?

Go to Step 15

Go to Step 13

10

Inspect for poor connections at the harness connector of the rear wiper motor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 15

Go to Step 12

11

Repair the open in the accessory voltage supply circuit of the rear wiper relay. Refer to Connector Repairs and Wiring Repairs .

Did you complete the repair?

Go to Step 15

--

12

Replace the rear wiper motor. Refer to Liftgate Wiper Motor Replacement .

Did you complete the replacement?

Go to Step 15

--

13

Replace the BCM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 15

--

14

Replace the rear wiper relay. Refer to Relay Replacement .

Did you complete the replacement?

Go to Step 15

--

15
  1. Use the scan tool to clear the DTCs.
  2. Operate the vehicle within the conditions for running the DTC, as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK