GM Service Manual Online
For 1990-2009 cars only

This vehicle is equipped with an on-board diagnostic display feature capable of displaying DTCs using the 3 indicators on the rear parking assist display. After the bulb check has been completed, the red outside indicator flashes to indicate a malfunction with the system. The module disables operation of the ultrasonic rear parking assist (URPA) system under this condition.

In order to enter the diagnostic mode, complete the following actions:

  1. With the ignition turned OFF, short the rear parking assist diagnostic connector to ground while the vehicle is in PARK. Refer to Passenger Compartment/Roof Component Views or Luggage Compartment/Rear of Vehicle Component Views for the location of the rear parking assist diagnostic connector.
  2. Turn the ignition ON.
  3. Place your foot on the brake.
  4. Shift the vehicle into REVERSE within 5 seconds.
  5. If the vehicle is not shifted into reverse within 5 seconds after turning the ignition ON, the diagnostic mode will still be initiated. However, a reverse input wiring fault will be registered as sequence #7 as shown in the Diagnostic Indicator table below. Refer to Diagnostic Trouble Code (DTC) Clearing for specific steps on how to clear DTCs. After the reverse input wiring code is cleared, repeat the DTC displaying steps in order to enter the diagnostic mode.

When the diagnostic mode is first entered, the rear parking assist display displays the amber outside indicator and the red outside indicator. Then the indicators on the rear parking assist display will display one or more of the sequences in the table below to indicate where the fault exists within the rear parking assist system. Refer to Diagnostic Trouble Code (DTC) Clearing for the specific steps on how to clear diagnostic trouble codes.

DTC Displaying

#

State/Fault Location

Amber Outside

Amber Middle

Red Outside

Flashing

1

Start of Diagnostics

X

--

X

--

2

RR Corner Object Sensor and Wiring

X

--

--

--

3

RR Middle Object Sensor and Wiring

X

X

--

--

4

LR Middle Object Sensor and Wiring

--

X

X

--

5

LR Corner Object Sensor and Wiring

--

--

X

--

6

Chime Alarm Wiring

--

X

--

--

7

Reverse Input Wiring

--

X

--

X

8

Note: This diagnostic pattern sets for an open sensor supply voltage circuit and sensor low reference circuit.

Sensor Supply Voltage Circuit and Sensor Low Reference Circuit

X

X

X

X

Flashes in the following sequence:

  1. Amber Outside
  2. Amber Outside and Amber Middle
  3. Amber Middle and Red Outside
  4. Red Outside

9

Note: This diagnostic pattern sets for a short to ground in the sensor supply voltage circuit.

Sensor Supply Voltage Circuit

X

X

X

--