GM Service Manual Online
For 1990-2009 cars only

Entering Self-Diagnostic Information

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

In order to enter the diagnostic mode you must short the rear parking assist diagnostic connector to ground, turn the ignition ON, and put the vehicle in REVERSE. When the diagnostic mode is first entered, the rear parking assist display, displays the amber (outside) indicator and the red (outside) indicator. After the start of diagnostic mode is complete, the indicators on the rear parking assist display will display one or more of the encoded messages in the table below to indicate where the fault exists within the rear parking assist feature. The specific steps to clear the encoded messages are provided below.

Clearing Self-Diagnostic Information

URPA encoded messages may be cleared in one of the following ways:

Vehicle Moving

  1. The stored messages will not clear if the rear parking assist diagnostic connector is grounded.
  2. Drive the vehicle forward at least 24 km/h (15 mph).
  3. Stop the vehicle.
  4. Turn OFF the ignition.

Vehicle Stopped

  1. The stored messages will not clear if the rear parking assist diagnostic connector is grounded.
  2. Turn ON the ignition, then shift into REVERSE within five seconds.
  3. Turn OFF the ignition.

Diagnostic Indicators

#

State

Amber (Outside)

Amber (Middle)

Red (Outside)

Flashing

1

Start of Diagnostics

X

--

X

--

2

Object Sensor Control Module and Wiring

X

X

X

--

3

RR Corner Object Sensor and Wiring

X

--

--

--

4

RR Middle Object Sensor and Wiring

X

X

--

--

5

LR Middle Object Sensor and Wiring

--

X

X

--

6

LR Corner Object Sensor and Wiring

--

--

X

--

7

Chime Warning Wiring

--

X

--

--

8

Reverse Input Wiring

--

X

--

X

Chimes 4 times

9

Display, Wiring, or Module

--

--

--

--

10

Supply Voltage to Sensor

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)

11

Supply Voltage to Sensor

X

X

X

--

12

Low Reference to Sensor

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)

13

Low Reference to Sensor

X

X

X

--