Circuit/System Testing
WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. 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 20 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 20 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.