Circuit/System Testing

WARNING: This page is about a different car, the 2013 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

Diagnose any antilock brake system (ABS) related DTCs before performing this diagnostic.

Ignition OFF, disconnect the X4 harness connector at the A11 radio.
Ignition ON.
Test for less than 1 V between the signal circuit terminal 20 and ground.
- If 1 V or greater
1. Ignition OFF, disconnect the harness connector at the K17 electronic brake control module. Ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
  - If 1 V or greater, repair the short to voltage on the circuit.
  - If less than 1 V, replace the K17 electronic brake control module.
- If less than 1 V
Test for 3-7 Hz between the signal circuit terminal 20 and ground while operating the vehicle drive wheels at 5 mph (8 km/h).
- If not 3-7 Hz
1. Ignition OFF, disconnect the harness connector at the K17 electronic brake control module.
2. Test for infinite resistance between the signal circuit and ground.
  - If less than infinite resistance, repair the short to ground on the circuit.
  - If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
  - If 2 Ω or greater, repair the open/high resistance in the circuit.
  - If less than 2 Ω, replace the K17 electronic brake control module.
- If 3-7 Hz
Test or replace the A11 radio.