B3626

DTC B3626

Circuit Description

The TC2 mode switch is a momentary-contact switch that can be used to limit the traction control function. Each time the TC2 mode switch is pressed, the TC2 switch full traction limited status changes. When the TC2 mode switch is released, voltage on the TC2 mode switch signal circuit is approximately 12 volts. When the TC2 mode switch is pressed, voltage on the TC2 mode switch signal circuit is approximately 0.5 volt.

DTC Descriptor

This diagnostic procedure supports the following DTCs:

DTC B3626 Traction Control Preference Switch Circuit

Conditions for Running the DTC

In order to detect a continuously low or high TC2 mode switch signal:

The ignition is ON.

OR

In order to detect a continuously pressed TC2 mode switch:

* The ignition is ON.
* The engine speed is greater than 450 RPM.

Conditions for Setting the DTC

Either of the following conditions may cause DTC B3626 to set:

* The TC2 mode switch signal is detected as excessively low or high for 200 milliseconds.
* The TC2 mode switch is detected as pressed for 60 seconds.

Action Taken When the DTC Sets

* The electronic brake control module (EBCM) disables the traction assist.
* The traction control system (TCS) light emitting diode (LED) switch telltale is disabled.

Conditions for Clearing the DTC

The conditions for setting the DTC are no longer present and the scan tool Clear DTCs function is used.

Diagnostic Aids

Press and release the TC2 mode switch several times while observing the traction LED switch telltale in order to verify that the TC2 full traction limited status changes each time the switch is pressed and that DTC B3626 does not set. Using the scan tool in order to observe the Mode Switch Pressed or Released status may also be helpful in diagnosing an intermittent fault within the switch.

Thoroughly inspect connections or circuitry that may cause an intermittent malfunction.

Test Description

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

4. This step tests for voltage on the TC2 mode switch signal circuit indicating an unpressed TC2 mode switch.
5. This step tests for voltage on the TC2 mode switch signal circuit indicating a pressed TC2 mode switch.

Step 1 - Step 7:

Step 8 - Step 14: