GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The intermittent switch in the windshield wiper washer switch is a voltage divider connected across the body control module (BCM) inputs circuits windshield wiper switch signal circuit and windshield wiper switch low reference circuit. The front wiper relay is energized by the BCM switching the front wiper relay control circuit to ground.

The intermittent wiper delay switch has 3 switch positions.

    • Delay 1 (500 ohms resistance)
    • Delay 2 (1000 ohms resistance)
    • Delay 3 (2000 ohms resistance)

Refer to Wiper/Washer System Description and Operation for the timing of each delay position.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B3702 Intermittent Wiper Delay Input Circuit Low

Conditions for Running the DTC

The ignition is in RUN or ACC position.

Conditions for Setting the DTC

The windshield wiper switch signal circuit is shorted to ground or less than 0.20 volt.

Actions Taken When the DTC Sets

    • No light will illuminate in the instrument panel (I/P).
    • Cannot vary wiper speed
    • B3702 is set in the BCM.

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 wiring harness for damage. Inspect for broken or chaffed insulation.
    • If fault is suspected to be intermittent, wiggling harness wiring may help in locating fault.
    • 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 is crimped over wire insulation and not conductors.

Step

Action

Values

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 ON the ignition, with the engine OFF.
  2. With a scan tool, observe the wiper delay input in the body control module (BCM) wiper/washer data list.

Is the voltage less than the specified value?

0.4 V

Go to Step 3

Go to Diagnostic Aids

3

  1. Turn OFF the ignition.
  2. Disconnect the windshield wiper washer switch.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the wiper delay input in the BCM wiper/washer data list.

Is the voltage greater than the specified value?

4.5 V

Go to Step 6

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Disconnect the BCM connector C2.
  3. Check continuity between the windshield wiper switch signal circuit and ground, then between the windshield wiper switch signal circuit and the windshield wiper low reference circuit.

Is there continuity?

--

Go to Step 5

Go to Step 7

5

Repair a short to ground in the windshield wiper switch signal circuit. Refer to Wiring Repairs or Connector Repairs .

Did you complete the repair?

--

Go to Step 8

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6

Replace the windshield wiper washer switch. Refer to Turn Signal Multifunction Switch Replacement .

Did you complete the replacement?

--

Go to Step 8

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7

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

Did you complete the replacement?

--

Go to Step 8

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8

  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