Circuit/System Testing
WARNING: This page is about a different car, the 2009 GMC Sierra and 2009 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- Remove connector from the tow/haul switch. Using the J 35616
GM-approved terminal test kit, install a fused jumper wire from the tow/haul switch signal and ground circuits of the tow/haul switch connector.
- If the scan tool Tow/Haul Mode indicates a status change, replace the switch.
- Using the DMM and the J 35616
, measure the voltage at the tow/haul switch signal circuit of the tow/haul switch connector.
- If Ignition Voltage is measured, test the ground circuit of the tow/haul switch for an open or shorted condition.
- Using the DMM and the J 35616
, measure the voltage at the tow/haul switch signal circuit of the body control module (BCM).
- If Ignition Voltage is measured, test the signal circuit of the tow/haul switch for an open or shorted condition.
- If Ignition Voltage is not measured, replace the BCM.