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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2007 🢒 Terrain 🢒 Safety and Security 🢒 Object Detection 🢒 On-Board Diagnostic Features

Self Sensor Error Check

Circuit Description

If system fault is detected by warning indicator or the alarm, perform the diagnosis for sensor circuit before the other circuits in the parking assist system. The parking assist control module can perform the error check for the each rear object sensor by using self sensor error check mode. Below is the procedure that should be performed in order to enter the sensor error check mode.

  1. Turn the ignition ON.
  2. Turn the parking brake switch On/Off over 3 times by locking and unlocking the parking brake over 3 times within 10 seconds after the ignition switch is turned ON.
  3. The control module will start the sensor error check mode.

Sensor Error Alarm Pattern

If the sensor circuit fault is not detected, control module will ring the normal alarm (1 time for 0.3 second). If the sensor circuit fault is detected, the alarm pattern will follow the table below according to the faulty sensor circuit.

Left Corner Sensor

A 40 ms tone with 1 second pause

Left Middle Sensor

Two 40 ms tones followed by a 1 second pause

Right Middle Sensor

Three 40 ms tones followed by a 1 second pause

Right Corner Sensor

Four 40 ms tones followed by a 1 second pause

    • 1 cycle is 3 seconds.
    • The alarm will perform the above sequence for 2 cycles.
    • If the fault is detected in several sensors, the control module will repeat the alarm pattern twice for the faulty sensors, following the order:
  1. Left Corner
  2. Left Middle
  3. Right Middle
  4. Right Corner

Step

Action

Value(s)

Yes

No

1
  1. Turn the ignition ON.
  2. Observe the parking assist warning indicator.

Does the indicator illuminate for 4 seconds and then off?

--

System OK

Go to Step 2

2
  1. Remove all objects at least 2 meters from the rear bumper.
  2. Start the sensor error check mode by turning the Indicator Check" parking brake switch On/Off over 3 times within 10 seconds after the ignition ON.

Does the alarm appear as the normal mode (only 1 time for 0.3 seconds)?

--

Go to Information Center Telltale Malfunction

Go to Step 3

3

Determine which sensor circuit(s) has the fault by referring to Sensor Error Alarm Pattern.

Do you find the suspected sensor circuit(s)?

--

Go to Step 4

--

4

Check for a poor connection on the suspected sensor(s).

Do you find and correct the condition?

--

Go to Step 11

Go to Step 5

5
  1. Turn the ignition OFF.
  2. Disconnect the connector of suspected sensor(s).
  3. Turn the ignition ON.
  4. Check the voltage the between the signal circuit and the low reference circuit of suspected sensor(s).

Is the voltage within the specified value?

8 V

Go to Step 8

Go to Step 6

6
  1. Turn the ignition OFF.
  2. Disconnect the connector of parking assist control module.
  3. Check for an open or a short to ground/B+ of the signal circuit at suspected sensor circuit(s).

Did you find and correct the condition?

--

Go to Step 11

Go to Step 7

7

Check for an open or a short to ground of the low reference circuit at suspected sensor circuit(s).

Do you find and correct the condition?

--

Go to Step 11

Go to Step 10

8

Check for a poor connection on the parking assist control module.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 9

9

Replace the suspected rear object sensor(s).

Did you the replacement?

--

Go to Step 11

--

10
  1. Replace the parking assist control module.
  2. Perform the BCM reprogramming procedure.

Did you complete the replacement?

--

Go to Step 11

--

11

Operate the system in order to verify the repair.

Did you correct the condition?

--

Go to Step 1

--