Circuit/System Testing
WARNING: This page is about a different car, the 2023 GMC Sierra 3500 HD and 2023 GMC Sierra 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition/Vehicle - Off
- Disconnect the electrical connector:S171R Instrument Panel Center Accessory Function Switch - Right
- Test for infinite resistance between the test points:Signal circuit terminal 12 (component side) & Ground circuit terminal 9 (component side)
- If less than infinite resistance
Replace the component:S171R Instrument Panel Center Accessory Function Switch - Right
- Go to next step: If infinite resistance
- If less than infinite resistance
- Press and hold the switch:Tow/Haul@S171R Instrument Panel Center Accessory Function Switch - Right
Test for less than 5 ohms between the test points:Signal circuit terminal 12 (component side) & Ground circuit terminal 9 (component side)
- If 5 ohms or greater
Replace the component:S171R Instrument Panel Center Accessory Function Switch - Right
- Go to next step: If less than 5 ohms
- If 5 ohms or greater
- Test for less than 10 ohms between the test points:Ground circuit terminal 9 (harness side) & Ground
- If 10 ohms or greater
- Disconnect the ground connection:G220
- Test for less than 2 ohms between the test points:Ground circuit terminal 9 (harness side) & Terminal G220
- If 2 ohms or greater - Repair the open/high resistance in the circuit.
- If less than 2 ohms - Repair the open/high resistance in the ground connection.
- Go to next step: If less than 10 ohms
- Disconnect the electrical connector:X7@K9 Body Control Module
- Ignition - On/Vehicle - In Service Mode
- Test for less than 1 V between the test points:Signal circuit terminal 12 (harness side) @S171R Instrument Panel Center Accessory Function Switch - Right & Ground
- If 1 V or greater
Repair the short to voltage on the circuit.
- Go to next step: If less than 1 V
- If 1 V or greater
- Ignition/Vehicle - Off
- Test for infinite resistance between the test points:Signal circuit terminal 12 (harness side) @S171R Instrument Panel Center Accessory Function Switch - Right & Ground
- If less than infinite resistance
Repair the short to ground on the circuit.
- Go to next step: If infinite resistance
- If less than infinite resistance
- Test for less than 5 ohms between the test points:Signal circuit terminal 12 (harness side) @S171R Instrument Panel Center Accessory Function Switch - Right & The other end of the circuit
- If 5 ohms or greater
Repair the open/high resistance in the circuit.
- Go to next step: If less than 5 ohms
- If 5 ohms or greater
- Replace the component:K9 Body Control Module