 | |
| Illustration 1 | g00864991 |
Schematic for the Parking Brake Pressure Switch | |
This diagnostic code is associated with the parking brake pressure switch. The switch is connected to two inputs of the ECM. One contact is open and the other contact is grounded during proper operation.
This FMI 03 means that the ECM has determined that the normally open contact and the normally closed contact are in the same state at the same time.
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.
System Response:
Machine Response: A level 3 warning will appear in the cab. The brake warning light will turn on. The alarm will sound. The transmission will shift to neutral, until the code is cleared, or operator does a parking brake drive-through.
Test Step 1. CHECK THE GROUND CIRCUIT OF THE SWITCH IN THE HARNESS
- Turn the key start switch and the disconnect switch to the OFF position.
- Disconnect the machine harness connector(s) from the ECM.
- Measure the resistance between contact J1-16 (wire 202-BK) of the machine harness for the ECM and the contact A (wire 202-BK).
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 5000 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 SWITCH CIRCUITS FOR A SHORT TO THE +BATTERY CIRCUIT
- Turn the disconnect switch and the key start switch to the OFF position.
- The machine harness remains disconnected from the switch.
- Disconnect the machine harness connector(s) from the ECM.
- Measure the resistance between contacts J1-27 (wire G764-PK) and J1-36 (wire 419-YL) of the machine harness to all the contacts that are used in machine harness connectors for the ECM.
Expected Result:
Each resistance measurement is greater than 5000 ohms.
Results:
- YES - Each resistance measurement is greater than 5000 ohms. Proceed to Test Step 3.
- NO - One or more of the resistance measurements are less than 5 ohms. The harness has failed. The short is between J1-27 (wire G764-PK) and the circuit with the lowest resistance or the short is between J1-36 (wire 419-YL) and the circuit with the lowest resistance.
Repair: Repair the wiring harness or replace the wiring harness.
STOP
Test Step 3. CHECK THE SWITCH CIRCUITS IN THE HARNESS
- The machine harness remains disconnected from the ECM and the switch.
- At the harness connector for the switch, connect a jumper wire between contact B (wire 419-YL) and contact C (wire G764-PK).
- At the harness connector for the ECM, measure the resistance from contact J1-27 (wire G764-PK) to contact J1-36 (wire 419-YL).
Expected Result:
The resistance is less than 5 ohms.
Results:
- OK - The resistance is less than 5 ohms. Proceed to Test Step 4.
- NOT OK - The resistance is greater than 5000 ohms. The circuit is open.
Repair: The machine harness has failed. Repair the machine harness or replace the machine harness.
STOP
Test Step 4. CHECK THE OPERATION OF THE SWITCH
- The machine harness remains disconnected from the switch.
- Connect one lead from a multimeter to contact A (wire 202-BK) of the harness connector for the switch.
- Connect the other lead from a multimeter to contact B (wire 419-YL) of the harness connector for the switch.
- Measure the resistance between contact A (wire 202-BK) and contact B (wire 419-YL). Note the resistance.
- Disconnect the lead from contact B (wire 419-YL) and connect the lead to contact C (wire G764-PK) .
- Measure the resistance between contact A (wire 202-BK) and contact C (wire G764-PK).
Expected Result:
The resistance from contact A (wire 202-BK) to contact C (wire G764-PK) is less than 5 ohms, and the resistance from contact (A) (wire 202-BK) to contact B (wire 419-YL) is greater than 5000 ohms.
Results:
- YES - The resistance from contact A (wire 202-BK) to contact C (wire G764-PK) is less than 5 ohms, and the resistance from contact A (wire 202-BK) to contact B (wire 419-YL) is greater than 5000 ohms. Proceed to Test Step 5.
- NO - The resistance measurements do not differ. The switch has failed.
Repair: Replace the switch.
STOP
Test Step 5. CHECK THE OPERATION OF THE SWITCH (HIGH PRESSURE)
- Start the engine. This will cause the system pressure to activate the primary steering pressure switch.
- Connect one lead from a multimeter to contact A (wire 202-BK) of the harness connector for the switch.
- Connect the other lead from a multimeter to contact B (wire 419-YL) of the harness connector for the switch.
- Measure the resistance between contact A (wire 202-BK) and contact B (wire 419-YL). Note the resistance.
- Disconnect the lead from contact B (wire 419-YL) and connect the lead to contact C (wire G764-PK).
- Measure the resistance between contact A (wire 202-BK) and contact C (wire G764-PK).
Expected Result:
The resistance from contact A to contact B is less than 5 ohms, and the resistance from contact A to contact C is greater than 5000 ohms.
Results:
- YES - The resistance from contact A to contact B is less than 5 ohms, and the resistance from contact A to contact C is greater than 5000 ohms. The switch is operating correctly. Proceed to Test Step 6.
- NO - The resistance from contact A to contact B is not less than 5 ohms, or the resistance from contact A to contact C is not greater than 5000 ohms. The switch has failed.
Repair: Replace the switch.
STOP
Test Step 6. CHECK IF THE DIAGNOSTIC CODE REMAINS
- Inspect the contacts of the harness connectors and clean the connectors.
- Reconnect all harness connectors.
- Turn the disconnect switch and the key start switch to the ON position.
- Operate the machine.
- Determine if CID 0627 FMI 03 is present.
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. See Testing And Adjusting, "Electronic Control Module (ECM) - Replace".
STOP
- NO - The CID 0627 FMI 03 is not active. The diagnostic code is NOT present. 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