Chassis Angle Sensor - Erratic, Intermittent, or Incorrect
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| Illustration 1 | g03387013 |
Schematic of the Body Pitch/Roll Sensor | |
The 1952-2 diagnostic code is associated with the chassis angle sensor which is also known as a body tilt pitch/roll sensor. The sensor communicates with the machine ECM via the CAN 3 Data Link. This diagnostic code is recorded when the machine ECM determines that the sensor data is erratic, intermittent, or incorrect.
Test Step 1. CHECK THE PLACEMENT OF THE PITCH/ROLL SENSOR
- Verify that the sensor is mounted securely to the body of the machine.
- Inspect the cable connection of the sensor. Confirm that the connector is secure and not damaged.
Expected Result:
The sensor and connector are securely in position.
Results:
- YES - The pitch/roll sensor is securely mounted to the machine. Proceed to Test Step 2.
- NO - The sensor body is not secure on the machine or the connector of the sensor is not secure.
Repair: Make necessary repairs based on observations.
STOP
Test Step 2. CHECK FOR AN OPEN IN THE CAN DATA LINK
- Place the key start switch and the disconnect switch in the OFF position.
- Disconnect the machine harness connectors "J1" and "J2" from the Machine ECM.
- At the harness connectors for the ECM, measure the resistance from contact "J2-45" (wire Y787-YL) to contact "C" of the quick disconnect. Measure the resistance from "J2-46" (wire Y788-GN) to contact "D" of the quick disconnect.
Expected Result:
Each resistance measurement is 60 (± 5) ohms.
Results:
- YES - Each resistance measurement is 60 (± 5) ohms. The circuit for the CAN data link is NOT open. Proceed to Test Step 3.
- NO - The resistance measurement is greater than 70 ohms. There is an open or a bad connection in the circuit for the CAN data link.
Repair: A resistance measurement that is greater than 5000 ohms could indicate that a wire is not connected or that a wire is open. A resistance greater than 70 ohms but less than 5000 ohms indicates a connection point is not open but is not a good connection. Refer to the complete Electrical System Schematic of the machine. Check all of the connectors that are in the circuit for the CAN data link. Ensure that all of the connections are clean, that all of the connections are secure and that all of the connections are in good condition. Repair the machine harness or replace the machine harness.
STOP
Test Step 3. CHECK THE CAN DATA LINK FOR A SHORT TO GROUND
- The key start switch and the disconnect switch remain in the OFF position.
- Disconnect the J1 and J2 connectors from the ECM.
- Measure the resistance between contact J2-45 (wire Y787-YL) and all pins on the machine harness. Measure the resistance between contact J2-46 (wire Y788-GN) and all pins on the machine harness. Note the resistance.
Expected Result:
The resistance measurements are greater than 5000 ohms.
Results:
- YES - Each resistance measurement is greater than 5000 ohms. The CAN data link is not shorted to another circuit in the machine harness.
Repair: Contact your technical communicator for a possible consultation with Caterpillar.
STOP
- NO - One or more of the resistance measurements is less than 5000 ohms. There is a short in the machine harness.
Repair: A wire in the circuit for the CAN data link is shorted. Refer to the complete Electrical System Schematic of the machine. Examine all of the connectors in the circuit. For additional information on testing short circuits and locating short circuits, refer to Testing and Adjusting, "Wiring Harness (Short Circuit) - Test". Repair the machine harness or replace the harness.
STOP