GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2003 🢒 Envoy - 2WD 🢒 Body and Accessories 🢒 Wipers/Washer Systems 🢒 Diagnostic System Check - Wiper/Washer

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. Lack of communication may be due to a partial malfunction of the class  2 serial data circuit or due to a total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.

    2.

  2. The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure will compile all the available information before tests are performed.

Step

Action

Yes

No

1

Install a scan tool.

Does the scan tool power up?

Go to Step 2

Go to Scan Tool Does Not Power Up in Data Link Communications

2

  1. Turn ON the ignition, with the engine OFF.
  2. Attempt to establish communication with the following systems:
    3. •  The body control module (BCM)
    • The liftgate control module (LCM)
    • The powertrain control module (PCM)

Does the scan tool communicate with the listed systems?

Go to Step 3

Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications

3

Important: The engine may start during the following step. Turn OFF the engine as soon as you have observed the Crank power mode.

  1. Access the Class 2 Power Mode in the Diagnostic Circuit Check on the scan tool.
  2. Rotate the ignition switch through all positions while observing the Class 2 Power Mode on the scan tool. Refer to the Serial Data Power Mode table within the Body Control System Description and Operation in Body Control Systems, for a list of the power mode states that correspond to each ignition switch position.

Does the Class 2 Power Mode parameter reading match the ignition switch position for all the selected positions?

Go to Step 4

Go to Power Mode Mismatch in Body Control System

4

Select the display DTCs function on the scan tool for the following control modules;

    • Body control module
    • Liftgate control module
    • Powertrain control module

Does the scan tool display any DTCs?

Go to Step 5

Go to Symptoms - Wiper/Washer Systems

5

Does the scan tool display any DTCs which begin with a "U"?

Go to Diagnostic Trouble Code (DTC) List in Data Link Communications

Go to Step 6

6

Does the scan tool display DTC B1000?

Go to Diagnostic Trouble Code (DTC) List in Body Control System

Go to Step 7

7

Does the scan tool display DTC P0562 or P0563?

Go to Diagnostic Trouble Code (DTC) List in Engine Electrical

Go to Diagnostic Trouble Code (DTC) List