| |
| Illustration 1 | g01081634 |
|
Schematic of the parking brake oil pressure switch | |
This diagnostic code is associated with the parking brake oil pressure switch. This diagnostic code is recorded when the Power Train/Chassis Electronic Control Module (ECM) reads the voltage of the switch circuit as being abnormal. The circuit is shorted to +battery circuit.
The possible causes of this diagnostic code are listed:
- The circuit J1-26 (wire G756-YL(Yellow)) is shorted to the +battery circuit.
- The circuit J1-26 (wire G756-YL(Yellow)) is open.
- The switch has failed.
- The ECM has failed. This is unlikely.
Note: The following test procedure may create other diagnostic codes. Ignore these diagnostic codes and clear the diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 0627 FMI 03 is active before performing this procedure.
Test Step 1. CHECK THE GROUND CIRCUIT OF THE SWITCH IN THE HARNESS
- Turn the key start switch and the battery disconnect switch to the OFF position.
- Disconnect the machine harness connector(s) J1 and J2 from the ECM.
- Disconnect the machine harness connector from the sensor.
- Measure the resistance between contact J1-26 (wire G756-YL(Yellow)) of the machine harness to contact B (wire G756-YL(Yellow)).
Expected Result:
The resistance is less than 5 ohms.
Results:
- OK - The resistance is less than 5 ohms. The circuit is correct. Proceed to Test Step 2.
- NOT OK - The resistance is greater than 5 ohms. The circuit is open. The machine harness has failed.
Repair: Repair the machine harness or replace the machine harness.
STOP
Test Step 2. CHECK THE SIGNAL CIRCUIT FOR A SHORT TO THE +BATTERY CIRCUIT.
- The key start switch and the battery disconnect switch to remain in the OFF position.
- Machine harness to remain disconnected from the ECM and the sensor.
- At machine harness connector J1 and J2, measure the resistance. Measure the resistance from the signal contact J1-26 (wire G756-YL(Yellow)) to all possible sources of +battery.
Expected Result:
The resistance is greater than 5 ohms for each measurement.
Results:
- OK - The resistance is greater than 5 ohms for each measurement. Proceed to Test Step 3.
- NOT OK - The resistance is less than 5 ohms. There is a short in the machine harness. The short is between signal contact J1-26 (wire G756-YL(Yellow)) and the circuit with the low resistance measurement.
Repair: Repair the harness or replace the harness.
STOP
Test Step 3. CHECK THE SWITCH.
- Reconnect the machine harness connectors J1 and J2 to the ECM.
- Turn the battery disconnect switch and the key start switch to the ON position.
- Ensure that the diagnostic code is active.
- Place a jumper wire between the (wire G756-YL(Yellow)) and to (wire 202-BK(Black)) of the switch.
Expected Result:
The status of the diagnostic code is active and the status of the diagnostic code is not active as the jumper wire is installed and the jumper wire is removed.
Results:
- OK - The diagnostic code changes from an active state to a inactive state. The switch has failed.
Repair: Repeat this test "CHECK THE SWITCH" in order to verify that the switch has failed. Replace the switch.
STOP
- NOT OK - The diagnostic code remains active. Proceed to Test Step 4.
Test Step 4. CHECK IF THE DIAGNOSTIC CODE REMAINS
- Inspect the contacts of the harness connectors and clean the harness connectors.
- Reconnect all the harness connectors.
- Turn the battery disconnect switch and the key start switch to the ON position.
- Operate the machine.
- Check the status of the CID 0627 FMI 03.
Expected Result:
The CID 0627 FMI 03 is active.
Results:
- YES - The CID 0627 FMI 03 is active. The diagnostic code has not been corrected. The ECM may have failed.
Repair: It is unlikely that the ECM has failed. Exit this procedure and perform this procedure again. If the cause of the diagnostic code is not found, replace the ECM. Refer to Systems operation, Troubleshooting, Testing and Adjusting, "Electronic Control Module (ECM) - Replace" for the machine that is being serviced.
STOP
- NO - The CID 0627 FMI 03 is not active. The diagnostic code does not exist at this time.
Repair: The initial diagnostic code was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation.
STOP