The electronic stability program (ESP) switch is a normally open switch that closes when the switch is activated. When activated, the switch grounds the ESP signal circuit. The body control module (BCM) converts the signal into serial data, which is used by the electronic brake control module (EBCM) to enable/disable the ESP. ESP status is displayed on the instrument cluster.

The BCM detects the ESP switch is activated for 60 seconds or more.

The multi function display (MFD) displays the ESP Off message.

Schematic Reference

Antilock Brake System Schematics .

Connector End View Reference

Component Connector End Views

Electrical Information Reference

Scan Tool Reference

Control Module References

With the vehicle in park or neutral, handbrake applied, and engine running observe the scan tool while operating the ESP switch. The scan tool display should switch from ESP ON to OFF as the switch is switched between states.

1. Verify that no other DTCs are set.
2. Ignition ON, using the scan tool observe the ESP parameter while activating/deactivating the ESP switch. The scan tool should verify a change of state in the ESP system.

⇒	If the ESP does not change state, disconnect the ESP/TCS switch harness connector. Connect a test light between a known ground and the signal circuit of the wiring harness.

⇒	If test light does not illuminate test the signal circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the BCM.

3. Reconnect the wiring harness to the ESP/TCS.
4. Test for less than 1 ohm resistance between the ESP/TCS switch ground circuit and a known ground.

⇒	If greater than specified range, test the ESP/TCS ground circuit for open/high resistance. If the circuit tests normal, replace the ESP/TCS switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.