Pinpoint Test H: DTC C1992
Parking Aid
Pinpoint Tests
Pinpoint Test H: DTC C1992
Refer to Wiring Diagram Set 131, Parking Aid for schematic and connector information. Diagrams By Number
Normal Operation
With the ignition switch in the RUN position, and the gear selector in REVERSE (R), the parking aid system calculates the distance to an object by the use of a radar sensor. The Parking Aid Module (PAM) receives a Vehicle Speed Sensor (VSS) signal, on circuit 679 (GY/BK), from the PCM indicating the vehicle speed. At or below 4.0 km/h (2.5 mph) the sensor can detect objects up to 255 cm (8 ft) to the rear of the vehicle, 50 cm (1.6 ft) to the rear side of the vehicle, and 16 cm (6 in) above ground.
- DTC C1992 (Vehicle Speed Circuit Failure) - a continuous and on-demand DTC that sets if the PAM detects an open or short to ground on the VSS circuit 679 (GY/BK).
Possible Causes
- Wiring, terminals or connectors
- Parking aid system wiring harness
- PAM
- PCM
- Audio Control Module (ACM)
- Liftgate/Trunk Module (LTM)
PINPOINT TEST H: DTC C1992
NOTICE: Use the correct probe adaptor(s) when making measurements. Failure to use the correct probe adaptor(s) may damage the connector.
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H1 CHECK THE RECORDED DTCs FROM BOTH THE CONTINUOUS AND ON-DEMAND PAM SELF-TESTS
- Check the recorded DTCs from the PAM self-test.
- Are any DTCs recorded?
Yes
If DTC C1992, GO to H2.
All other DTCs, REFER to DTC Charts. [1][2]Diagnostic Trouble Code Descriptions
No
Go To Pinpoint Test A. Pinpoint Test A: Parking Aid Is Inoperative
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H2 CHECK FOR A VSS CIRCUIT FAULT WITH THE ACM DISCONNECTED
- Ignition OFF.
- Disconnect: ACM C290a.
- Ignition ON.
- Retrieve the recorded PAM DTCs from the on-demand self-test.
- Is DTC C1992 recorded?
Yes
If equipped with an LTM, GO to H3. Otherwise, GO to H4.
No
INSTALL a new ACM.
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H3 CHECK FOR A VSS CIRCUIT FAULT WITH THE LTM DISCONNECTED
- Ignition OFF.
- Disconnect: LTM C4081c.
- Ignition ON.
- Retrieve the recorded PAM DTCs from the on-demand self-test.
- Is DTC C1992 recorded?
Yes
GO to H4.
No
INSTALL a new LTM.
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H4 CHECK THE VSS CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: PAM C4014.
- Disconnect: PCM C175b.
- Measure the resistance between the PCM C175b-1, circuit 679 (GY/BK), harness side and the PAM C4014-12, circuit 679 (GY/BK), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to H5.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
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H5 CHECK THE VSS CIRCUIT FOR A SHORT TO GROUND
- Measure the resistance between the PAM C4014-12, circuit 679 (GY/BK), body harness side and ground.
- Is the resistance less than 5 ohms?
Yes
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
No
GO to H6.
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H6 CHECK FOR CORRECT PCM OPERATION
- Connect: All Disconnected Connectors.
- Disconnect the PCM connector.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect the PCM connector and make sure it seats correctly.
- Operate the system and determine if the concern is still present.
- Is the concern still present?
Yes
INSTALL a new PCM. TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.
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