Circuit/System Testing
WARNING: This page is about a different car, the 2019 GMC Savana 3500, 2019 GMC Savana 2500, 2019 Chevrolet Express 3500, and 2019 Chevrolet Express 2500. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition/Vehicle - Off
- Disconnect the electrical connector : K9 Body Control Module
- Ignition - On / Vehicle - In Service Mode
- Momentarily connect a 3 A fused jumper wire between the test points : Control circuit terminal 18 X5 & Ground
Verify the component turns On and Off when connecting and disconnecting the jumper wire : P13 Horn Assembly
- If the component does not turn On and Off
- Ignition/Vehicle - Off & Remove - Jumper wire(s)
- Disconnect the electrical connector : X3 @ X50A Fuse Block - Underhood
- Ignition - On / Vehicle - In Service Mode
- Test for less than 1 V between the test points : Control circuit terminal 18 X5 @ Control module harness & Ground
- If 1 V or greater - Repair the short to voltage on the circuit.
- Go to next step : If less than 1 V
- Ignition/Vehicle - Off
- Test for infinite resistance between the test points : Control circuit terminal 18 X5 @ Control module harness & Ground
- If less than infinite resistance - Repair the short to ground on the circuit.
- Go to next step : If infinite resistance
- Test for less than 2 ohms between the test points : Control circuit terminal 18 X5 @ Control module harness & Control circuit terminal H3 X3 @ Fuse Block Harness
- If 2 ohms or greater - Repair the open/high resistance in the circuit.
- If less than 2 ohms - Test or replace the component : X50A Fuse Block - Underhood
- Go to next step : If the component turns On and Off
- Replace the component : K9 Body Control Module