Pinpoint Test C: DTC C1742 or DTC C1743
Parking Aid - Expedition
Pinpoint Tests
Pinpoint Test C: DTC C1742 or DTC C1743
Refer to Wiring Diagram Set 131, Parking Aid for schematic and connector information. Diagrams By Number
Normal Operation
The parking aid speaker tone is controlled by the Parking Aid Module (PAM). When the parking aid system detects an object to the rear of the vehicle, the parking aid speaker sounds an audible tone to notify the driver that an object is present.
- DTC C1742 (Rear Sounder Circuit Failure) - a continuous and on-demand DTC that sets if the PAM detects a short to ground or open on the rear speaker circuit CLS03 when the vehicle is in REVERSE (R) and a detectable object is within the azimuth field.
- DTC C1743 (Rear Sounder Circuit Short To Vbatt) - a continuous and on-demand DTC that sets if the PAM detects a short to voltage on the rear speaker circuit CLS03 when the vehicle is in REVERSE (R) and a detectable object is within the azimuth field.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Parking aid speaker
- PAM
PINPOINT TEST C: DTC C1742 OR DTC C1743
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to Battery.
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C1 CHECK THE RECORDED PAM DTCs FROM BOTH THE CONTINUOUS AND ON-DEMAND SELF-TESTS
- Check the recorded PAM DTCs from the continuous and on-demand self-tests.
- Is DTC C1742 or DTC C1743 recorded?
Yes
GO to C2.
No
REFER to DTC Charts. Parking Aid
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C2 MEASURE THE PARKING AID SPEAKER RESISTANCE
- Ignition OFF.
- Disconnect: Parking Aid Speaker C4015.
- Measure the resistance between the parking aid speaker pin 1, component side and the parking aid speaker pin 2, component side.
- Is the speaker resistance between 45 and 57 ohms?
Yes
For DTC C1742, GO to C3.
For DTC C1743, GO to C6.
No
INSTALL a new parking aid speaker. REFER to Parking Aid Speaker - Expedition Service and Repair. CLEAR the DTCs. REPEAT the self-test.
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C3 CHECK THE PARKING AID SPEAKER (+) CIRCUIT FOR A SHORT TO GROUND
- Measure the resistance between the PAM C4226-15, circuit CLS03 (GN/WH), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to C4.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
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C4 CHECK THE PARKING AID SPEAKER (+) CIRCUIT FOR AN OPEN
- Measure the resistance between the PAM C4226-15, circuit CLS03 (GN/WH), harness side and the parking aid speaker C4015-2, circuit CLS03 (GN/WH), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to C5.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
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C5 CHECK THE PARKING AID SPEAKER GROUND CIRCUIT FOR AN OPEN
- Disconnect: Parking Aid Speaker C4015.
- Disconnect: Negative Battery Cable.
- Measure the resistance between the parking aid speaker C4015-1, circuit GD149 (BK/GY), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to C7.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
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C6 CHECK THE PARKING AID SPEAKER (+) CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Connect: Negative Battery Cable.
- Disconnect: PAM C4226.
- Measure the voltage between the PAM C4226-15, circuit CLS03 (GN/WH), harness side and ground.
- Is any voltage indicated?
Yes
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
No
GO to C7.
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C7 CHECK FOR CORRECT PAM OPERATION
- Connect: All Disconnected Connectors.
- Disconnect the PAM connector.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect the PAM 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 PAM. REFER to Parking Aid Module (PAM) - Expedition Service and Repair. 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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