GM Service Manual Online
For 1990-2009 cars only

Use the scan tool data display values and definitions information in order to assist in diagnosing vehicle malfunctions. Compare the vehicles actual scan tool data display with the typical data value in the table. Use the data in order to aid in understanding the nature of the concern when the vehicle data display does not match the typical data values. Refer to Scan Tool Data List .

The typical scan tool data values were taken from a known good vehicle under the following conditions:

    • The ignition switch is in the ON position.
    • The windshield wiper/washer switch is OFF.
Battery Voltage Signal: The scan tool displays the state of the battery voltage level.

Windshield Washer Switch: The body control module (BCM) uses this input to determine if the wash switch is pressed. If it is pressed, the scan tool will display Active and the BCM will command the wiper micro relay ON and keep it ON until 2 wipe cycles have completed after the switch has been released.

Windshield Wiper Switch: The body control module (BCM) uses this input to determine if the wiper switch is activated. If it is activated, the scan tool will display ON and the wipers will operate in delay, low, or high speed depending on switch position.

Wiper Motor Delay Time: The scan tool displays the delay duration time of each delay switch position. When the first position is selected, the scan tool displays 11 seconds and reduces the delay time by 2 seconds for each subsequent position selection. When the windshield wiper switch is OFF, the scan tool will display 0 seconds.

Wiper Motor Relay Command: The scan tool displays ON when the BCM commands wiper motor relay activation.

Wiper Motor Relay Status: The scan tool displays the state of the wiper motor relay. The scan tool will display ON when the wipers are in operation.

Wiper Park Switch: The BCM uses this input to determine if the wipers are approaching the park position. The scan tool displays Inactive when the BCM detects ground on the windshield wiper motor park switch signal circuit.

Wiper Switch: The BCM uses this input to determine which mode to operate the wipers. The scan tool displays 0 volts in OFF, approximately 0.65 volts to 2.16 volts in the DELAY positions, approximately 2.86 volts in LO, and approximately 2.84 volts in HI.