B0956
DTC B0954, B0955, B0956, or B0957
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using the diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions)provides an overview of each diagnostic category.
DTC Descriptors
DTC B0954 01
- Parking Aid Front Sensor 1 Circuit Short to Battery-Left Corner
DTC B0954 06
- Parking Aid Front Sensor 1 Circuit Short to Ground or Open-Left Corner
DTC B0954 21
- Parking Aid Front Sensor 1 Circuit Incorrect Period-Left Corner
DTC B0955 01
- Parking Aid Front Sensor 2 Circuit Short to Battery-Left Middle
DTC B0955 06
- Parking Aid Front Sensor 2 Circuit Short to Ground or Open-Left Middle
DTC B0955 21
- Parking Aid Front Sensor 2 Circuit Incorrect Period-Left Middle
DTC B0956 01
- Parking Aid Front Sensor 3 Circuit Short to Battery-Right Middle
DTC B0956 06
- Parking Aid Front Sensor 3 Circuit Short to Ground or Open-Right Middle
DTC B0956 21
- Parking Aid Front Sensor 3 Circuit Incorrect Period-Right Middle
DTC B0957 01
- Parking Aid Front Sensor 4 Circuit Short to Battery-Right Corner
DTC B0957 06
- Parking Aid Front Sensor 4 Circuit Short to Ground or Open-Right Corner
DTC B0957 21
- Parking Aid Front Sensor 4 Circuit Incorrect Period-Right Corner
Diagnostic Fault Information
Circuit/System Description
The object sensors are 3-wire sensors that are used to determine the distance between the vehicle and an object of interest. The object alarm module supplies 8 volts to the object sensors via the 8 volt reference circuit and provides ground via the low reference circuit. The object alarm module triggers the sensors in a sequential loop. After each sensor transmits, the object alarm module uses the sensor ring received through the signal circuit to calculate the distance and position of an object.
Conditions for Running the DTC
* DTC B1325 is not set
* Ignition voltage is between 9 - 16 V
* The vehicle is in DRIVE
Conditions for Setting the DTC
B0954 01, B0955 01, B0956 01, or B0957 01
Voltage seen on the object sensor signal circuit is greater than 11.5 V.
B0954 06, B0955 06, B0956 06, or B0957 06
Voltage seen on the object sensor signal circuit is less than 0.5 V.
B0954 21, B0955 21, B0956 21, or B0957 21
The object sensor determines no change in the position of an object while the vehicle is in motion.
Action Taken When the DTC Sets
* Parking assist is disabled.
* The object alarm module commands the red indicator ON.
* The object alarm module sends a serial data message to the instrument panel cluster (IPC) to display SERVICE PARK ASSIST message in the driver information center (DIC) and a chime will sound.
Conditions for Clearing the DTC
* The DTC will transition to history when the fault is no longer present.
* A history DTC will clear after 100 malfunction-free ignition cycles.
Reference Information
Schematic Reference
Object Detection Schematics ([1][2]Collision Avoidance and Parking Assist Systems)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Object Detection Description and Operation (UFL) (Object Detection Description and Operation (UFL))Object Detection Description and Operation (UFR) (Object Detection Description and Operation (UFR))Object Detection Description and Operation (UFT) (Object Detection Description and Operation (UFT))
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Testing for Intermittent Conditions and Poor Connections (Testing For Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
* Connector Repairs (Connector Repairs)
Scan Tool Reference
Control Module References (Programming and Relearning)for scan tool information
Circuit/System Verification
1. Verify that DTC B138A is not set.
• If DTC is set, refer to DTC B138A (B138A).
2. Park brake OFF, transmission in DRIVE, individually place an object in front of each sensor. Verify the appropriate scan tool Front Region parameter is between Zone 1 and Zone 4.
Circuit/System Testing
Single Object Sensor DTC Set
1. Ignition OFF, disconnect the harness connector at the appropriate object sensor.
2. 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.
3. Ignition ON, transmission in DRIVE, test for 8.0 - 9.0 V 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.
4. Ignition OFF, remove the malfunctioning object sensor and swap locations with another properly functioning object sensor. Connect the harness connector at both sensors.
5. 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.
6. If the DTC sets for the new location in which the malfunctioning sensor is installed, replace the appropriate object sensor.
Multiple Object Sensor DTCs Set
1. Ignition OFF, disconnect the harness connector at each of the object sensors.
2. 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.
3. Ignition ON, transmission in DRIVE, test for 8.0 - 9.0 V 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.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Front Object Alarm Sensor Replacement (Front Object Alarm Sensor Replacement)
* Control Module References (Programming and Relearning)for object alarm module replacement, setup, and programming