Circuit/System Testing
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2008 GMC Yukon XL, 2008 GMC Yukon, 2008 Chevrolet Tahoe, 2008 Chevrolet Suburban, and 2008 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
Single Object Sensor DTC Set
- Ignition OFF, disconnect the harness connector at the appropriate object sensor.
- Ignition OFF for 30 seconds, test for less than 5 ohms between the low reference circuit terminal 2 and ground.
- If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the object alarm module.
- Ignition ON, transmission in REVERSE, test for 8.0-9.0 volts between the voltage reference circuit terminal 1 and ground.
- If greater than the specified range, test the voltage reference circuit for a short to voltage. If the circuit tests normal, replace the object alarm module.
- If less than the specified range, test the voltage reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the object alarm module.
- Ignition OFF, remove the malfunctioning object sensor and swap locations with another properly functioning rear object sensor. Connect the harness connector at both sensors.
- Ignition ON, verify the DTC is set for the new location in which the malfunctioning sensor is installed.
- If the DTC does not set for the new location, test the signal circuit terminal 3 for a short to voltage, short to ground, or an open/high resistance. If the circuit tests normal, replace the object alarm module.
- If the DTC sets for the new location in which the malfunctioning sensor is installed, replace the appropriate rear object sensor.
Multiple Object Sensor DTCs Set
- Ignition OFF, disconnect the harness connector at each of the object sensors.
- Ignition OFF for 30 seconds, test for less than 5 ohms between the low reference circuit terminal 2 and ground.
- If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the object alarm module.
- Ignition ON, transmission in REVERSE, test for 8.0-9.0 volts between the voltage reference circuit terminal 1 and ground.
- If greater than the specified range, test the voltage reference circuit for a short to voltage. If the circuit tests normal, replace the object alarm module.
- If less than the specified range, test the voltage reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the object alarm module.