GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Schematic Reference: Rear Parking Assist Schematics

1

Did you review the operation and perform the necessary inspections?

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Go to Step 2

Go to Symptoms - Ultrasonic Rear Parking Assist

2

  1. Set the park brake.
  2. Turn ON the ignition, then shift into REVERSE within 5 seconds.

Do the three display indicators turn on for 2 seconds and then turn off during bulb check?

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Go to Step 3

Go to Step 4

3

Is the red indicator flashing after the bulb check?

--

Go to Step 12

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

4

Are all indicators inoperative during bulb check?

--

Go to Step 13

Go to Step 5

5

Is one indicator always on even after bulb check?

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Go to Step 14

Go to Step 15

6

Does diagnostic indicator pattern #3, 4, 5, or 6 On-Board Diagnostic Features appear as shown in the diagnostic indicator table?

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Go to Step 19

Go to Step 7

7

Does diagnostic indicator pattern #7 On-Board Diagnostic Features appear as shown in the diagnostic indicator table?

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Go to Step 20

Go to Step 8

8

Does diagnostic indicator pattern #8 On-Board Diagnostic Features appear as shown in the diagnostic indicator table?

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Go to Step 22

Go to Step 9

9

Does diagnostic indicator pattern #10 or 12 On-Board Diagnostic Features appear as shown in the diagnostic indicator table?

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Go to Step 23

Go to Step 10

10

Does diagnostic indicator pattern #11 or 13 On-Board Diagnostic Features appear as shown in the diagnostic indicator table?

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Go to Step 24

Go to Step 11

11

Does diagnostic indicator pattern #9 On-Board Diagnostic Features appear as shown in the diagnostic indicator table?

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Go to Step 25

Go to Step 26

12

  1. Turn OFF the ignition.
  2. Remove all objects, at least 2 meters, away from the rear bumper.
  3. Short the rear parking assist diagnostic connector to ground.
  4. Diagnostics have been entered at this point. Refer to On-Board Diagnostic Features for more information.

  5. Turn ON the ignition, then shift into REVERSE within 5 seconds.

Does diagnostic indicator pattern #1 On-Board Diagnostic Features appear as shown in the diagnostic indicator table when you enter diagnostics?

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Go to Step 6

Go to Step 32

13

Test the rear object sensor control module ground circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 33

Go to Step 16

14

Test the inoperative indicator control circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 33

Go to Step 32

15

Test the inoperative indicator control circuit for an open and a short to B+. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 33

Go to Step 32

16

Test the ignition 1 voltage circuit for an open and a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 33

Go to Step 17

17

Test the low reference object sensor circuit for a short to B+. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 33

Go to Step 18

18

Test the reverse relay circuit for a short to ground and a short to B+. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 33

Go to Step 29

19

Test the inoperative object sensor signal circuit for an open, a short to ground, and a short to B+. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 33

Go to Step 21

20

Test the rear parking assist chime signal circuit for an open and a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 33

Go to Step 32

21

Test the supply voltage and the low reference circuits of the inoperative object sensor for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 33

Go to Step 30

22

Test the reverse relay circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 33

Go to Step 32

23

Test the object sensor supply voltage and the object sensor low reference circuits for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 33

Go to Step 32

24

Test the object sensor supply voltage and the object sensor low reference circuits for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 33

Go to Step 32

25

Test the telltale assembly supply voltage circuit for an open, a short to ground, and a short to B+. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 33

Go to Step 27

26

Diagnostic indicator pattern #2 appears. Replace the rear object sensor control module. Refer to Object Alarm Module Replacement .

Did you complete the replacement?

--

Go to Step 33

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27

Test the VSS signal circuit for an open, a short to ground, and a short to B+. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 33

Go to Step 28

28

Test the rear parking assist chime signal circuit for a short to B+. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 33

Go to Step 32

29

Test the rear parking assist display for continuity. Refer to Circuit Testing in Wiring Systems.

Is there continuity?

--

Go to Step 32

Go to Step 31

30

Replace the inoperative object sensor. Refer to Rear Object Sensor Replacement .

Did you find and correct the condition?

--

Go to Step 33

Go to Step 32

31

Replace the rear parking assist display. Refer to Information Center Telltale Assembly Replacement .

Did you complete the replacement?

--

Go to Step 33

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32

Replace the rear object sensor control module. Refer to Object Alarm Module Replacement .

Did you complete the replacement?

--

Go to Step 33

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33

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 2