For 1990-2009 cars

# Park Assist System Inoperative, Service Park Assist Message on DIC, DTC B1E3A and/or B0954, P0955, B0956, B0957, B0958, B0959, B0960, B0961 (Replace Appropriate Object Sensor or Repair Harness)

Subject: | Park Assist System Inoperative, Service Park Assist Message on Driver Information Center (DIC), DTC B1E3A and/or B0954, B0955, B0956, B0957, B0958, B0959, B0960, B0961 (Replace Appropriate Object Sensor or Repair Harness)

Models: | 2006-2008 Buick Lucerne

| 2008-2009 Buick Enclave

| 2006-2008 Cadillac DTS

| 2007-2009 Cadillac Escalade, SRX

| 2008-2009 Cadillac CTS

| 2007-2009 Chevrolet Avalanche, Silverado, Suburban, Tahoe

| 2009 Chevrolet Traverse

| 2007-2009 GMC Acadia, Sierra, Yukon, Yukon XL

| 2007-2009 Saturn OUTLOOK

| Equipped with Parking Assist (RPO UD7 or UFR)

### Condition

Some customers may comment on a "Service Park Assist" message displayed on the DIC. Upon investigation, the technician may find DTC B1E3A and one or more of the following DTC's stored: B0954, B0955, B0956, B0957, B0958, B0959, B0960, B0961.

### Cause

This may be caused by a malfunctioning object sensor or a circuit fault on the 8 volt reference circuit.

Notice: The 8 volt reference circuit serves all of the object sensors in parallel. A fault anywhere on the circuit or in any single sensor will affect all of the sensors.

When a single sensor malfunctions, the shared 8 volt reference circuit may be compromised, resulting in a DTC for each sensor.

### Correction

Important: DO NOT replace all the sensors and/or the object alarm module.

If normal diagnosis does not reveal any concerns with the park assist system, perform the following diagnostic procedure:

1. Turn the ignition OFF and disconnect the harness connector at each of the park assist sensors (4 sensors except Cadillac DTS- 8 sensors)

Important: With all the park assist sensor harness connectors disconnected, multiple sensor DTCs will set and will not clear. Ignore these DTCs.

2. Turn the ignition ON, clear any DTC. Verify DTC B1E3A is not set after clearing the DTCs.

• | If the DTC B1E3A is set, test the 8 volt reference circuit for a short to voltage/power or a short to ground.

| Important: Ensure each leg of the circuit is tested since the 8 volt reference circuit feeds all the sensors in parallel.

• | Repair the faulty leg.

3. Install each sensor harness connector one at a time, checking DTCs after each sensor is connected. Verify DTC B1E3A is not set. If DTC B1E3A is set, replace the park assist sensor that was connected immediately before the DTC set.

### Parts Information

Part Number | Description | Quantity
--- | --- | ---
15239247 | Sensor Kit, RR Object | 1

### Warranty Information

For vehicles repaired under warranty, use:

Labor Operation | Description | Labor Time
--- | --- | ---
R4113 | Sensor, Front Object Alarm - Replace | Use Published Labor Operation Time
R4114 | Sensor, Rear Object - Replace | Use Published Labor Operation Time
N6620 | Wiring And/Or Connector- Power & Grounds - Repair Or Replace | Use Published Labor Operation Time