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| Illustration 1 | g01227022 |
Schematic of the parking brake switch (pull-to-engage) | |
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| Illustration 2 | g01227024 |
Schematic of the parking brake switch (push-to-engage) | |
Note: The following test procedure is applicable to the pull-to-engage parking brake switch and the push-to-engage parking brake switch.
This diagnostic code is associated with the parking brake switch. The switch is connected to two inputs of the ECM. One input is open and the other input is grounded during proper operation.
The FMI 04 means that the ECM has determined that both inputs are grounded.
Note: The following test procedure may create other diagnostic codes. Ignore these diagnostic codes and clear these diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 0070 FMI 04 is active before performing this procedure.
System Response:
The parking brake remains engaged when a failure exists for this diagnostic code.
Test Step 1. CHECK THE HARNESS FOR A SHORT CIRCUIT
- Turn the disconnect switch and the key start switch to the OFF position.
- Disconnect the harness connectors form the ECM and the switch.
- At the machine harness connector for the ECM, measure the resistance from connector contact 55 (wire G764-PK) to all the contacts that are used in the machine harness connectors for the ECM.
- At the machine harness connector for the ECM, measure the resistance from connector contact 54 (wire C976-YL) to all the contacts that are used in the machine harness connectors for the ECM.
Expected Result:
Each resistance measurement is greater than 5 ohms.
Results:
- YES - Each resistance measurement is greater than 5 ohms. The harness is correct. Proceed to Test Step 2.
- NO - One or more of the measurements were less than 5 ohms. There is a possible short in the machine harness.
Repair: The short is between wire C976-YL and the circuit with the lowest resistance measurement or the short is between wire G764-PK and the circuit with the lowest resistance measurement. Repair the machine harness or replace the machine harness.
STOP
Test Step 2. CHECK THE OPERATION OF THE SWITCH
- The disconnect switch and the key start switch remain in the OFF position.
- The harness connectors for the ECM remain disconnected.
- Reconnect the harness connector for the switch.
- Ensure the parking brake switch is in the ON position. (Engage the parking brake).
- At the machine harness connector for the ECM, measure the resistance from connector contact 54 (wire C976-YL) and frame ground.
- At the machine harness connector for the ECM, measure the resistance from connector contact 55 (wire G764-PK) and frame ground.
Expected Result:
The resistance from connector contact 55 (wire G764-PK) to frame ground is less than 5 ohms, and the resistance from connector contact 54 (wire C976-YL) to frame ground is greater than 5 ohms.
Results:
- YES - The resistance from connector contact 55 (wire G764-PK) to frame ground is less than 5 ohms, and the resistance from connector contact 54 (wire C976-YL) to frame ground is greater than 5 ohms Proceed to Test Step 3.
- NO - The resistance measurements do not differ for both contacts. The switch has failed.
Repair: Replace the switch.
STOP
Test Step 3. CHECK THE OPERATION OF THE SWITCH
- The disconnect switch and the key start switch remain in the OFF position.
- The harness connectors for the ECM remain disconnected.
- Reconnect the harness connector for the switch.
- Ensure the parking brake switch is in the OFF position. (Disengage the parking brake).
- At the machine harness connector for the ECM, measure the resistance from connector contact 54 (wire C976-YL) and frame ground.
- At the machine harness connector for the ECM, measure the resistance from connector contact 55 (wire G764-PK) and frame ground.
Expected Result:
The resistance from connector contact 54 (wire C976-YL) to frame ground is less than 5 ohms, and the resistance from connector contact 55 (wire G764-PK) to frame ground is greater than 5 ohms.
Results:
- YES - The resistance from connector contact 54 (wire C976-YL) to frame ground is less than 5 ohms, and the resistance from connector contact 55 (wire G764-PK) to frame ground is greater than 5 ohms. Proceed to Test Step 4.
- NO - The resistance measurements do not differ for both contacts. The switch has failed.
Repair: Replace the switch.
STOP
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 disconnect switch and the key start switch to the ON position.
- Operate the machine.
- Check the status of the CID 0070 FMI 04.
Expected Result:
The CID 0070 FMI 04 is active.
Results:
- YES - The CID 0070 FMI 04 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 Troubleshooting, Testing and Adjusting, "Electronic Control Module (ECM) - Replace".
STOP
- NO - The CID 0070 FMI 04 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