Circuit/System Testing

WARNING: This page is about a different car, the 2020 Buick Regal TourX, 2020 Buick Regal, 2019 Buick Regal TourX, and 2019 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.

Ignition/Vehicle & All vehicle systems - Off
Disconnect the electrical connector: X1 @ A11 Radio
Engine Running @ 600 RPM
Test for 575 to 800 Hz between the test points: Signal circuit terminal 23 & Ground
- If not between 575 and 800 Hz
1. Ignition/Vehicle & All vehicle systems - Off
2. Disconnect the appropriate electrical connector: @ K20 Engine Control Module
3. Ignition - On/Vehicle - In Service Mode
4. Test for less than 1 V between the test points: Signal circuit terminal 23 & Ground
  - If 1 V or greater - Repair the short to voltage on the circuit.
  - Go to next step: If less than 1 V
5. Ignition/Vehicle & All vehicle systems - Off
6. Test for infinite resistance between the test points: Signal circuit terminal 23 & Ground
  - If less than infinite resistance - Repair the short to ground on the circuit.
  - Go to next step: If infinite resistance
7. Test for less than 2 ohms between the test points: Signal circuit terminal 23 & The other end of the circuit
  - If 2 ohms or greater - Repair the open/high resistance in the circuit.
  - If less than 2 ohms - Replace the component: K20 Engine Control Module
- Go to next step: If between 575 and 800 Hz
Test or replace the component: A11 Radio