R1300G Load Haul Dump Power Train Electronic Control System Caterpillar

Illustration 1	g02373096
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.

The FMI 03 means that the ECM has determined that the normally open contact and the normally closed contact are open.

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 OPERATION OF THE SWITCH

Illustration 2	g02419900
LED indicator located on both sides of the switch

1. Turn the battery disconnect switch and the key start switch to the ON position.

   ReferenceRefer to Table 1 for LED indicator identification.

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   Table 1

   LED Status		LED Status		Key	Fault	Parking Brake Indicator
   ON	Green (1)	ON	Yellow (1)	ON	No	OFF
   ON	Yellow	ON	Green	ON	No	ON
   Flashes @ 2Hz	Green	Flashing @ 2Hz	Green	ON	Internal Fault	ON
   OFF		OFF		ON	Interrupted power supply to the switch	ON

   Show/hide table

   ( 1 )

   Color of LED's alternate when the parking brake status changes

Expected Result:

One LED is yellow and one LED is green.

Results:

• YES - One LED is yellow and one LED is green. The switch is operating correctly. Proceed to Test Step 4.

• NO - Both LED are OFF. Proceed to Test Step 2.

• NO - Both LED flash green at 2 Hz. The switch has failed.

  Repair: Replace the switch.

  STOP

Test Step 2. CHECK THE BATT+ CIRCUIT OF THE SWITCH IN THE HARNESS

1. Turn the key start switch and the battery disconnect switch to the OFF position.

2. Check the status of circuit breaker 2.

Expected Result:

Circuit breaker 2 has tripped.

Results:

• YES - Circuit breaker 2 has tripped.

  Repair: Repair (wire 113-OR) of the machine harness and reset circuit breaker 2.Tripped Circuit Breaker

  A tripped circuit breaker may be the result of a fault in another circuit. Refer to the Electrical System Schematic for related circuits.

  STOP

• NO - Circuit breaker 2 has not tripped. Proceed to Test Step 3.

Test Step 3. CHECK THE GROUND CIRCUIT OF THE SWITCH IN THE HARNESS

1. The key start switch and the battery disconnect switch remain in the OFF position.

2. Disconnect the machine harness connector from the switch.

3. Measure the resistance between frame ground (wire 202-BK) of the machine harness and the contact 3 (wire 202-BK).

Expected Result:

The resistance is greater than 5 ohms.

Results:

• YES - 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 4. CHECK THE HARNESS

1. Turn the key start switch and the battery disconnect switch to the OFF position.

2. Disconnect the machine harness from the switch.

3. Disconnect the machine harness connectors from the ECM.

4. Measure the resistance between contacts J1-37 (wire D735-PK) and J1-39 (wire D756-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 5 ohms.

Results:

• YES - Each resistance measurement is greater than 5 ohms. Proceed to Test Step 5.

• NO - One or more of the resistance measurements are less than 5 ohms. The harness has failed. The short is between J1-37 (wire D735-PK) and the circuit with the lowest resistance or the short is between J1-39 (wire D756-YL) and the circuit with the lowest resistance.

  Repair: Repair the wiring harness or replace the wiring harness.

  STOP

Test Step 5. CHECK THE SWITCH CIRCUITS IN THE HARNESS

1. The key start switch and the battery disconnect switch remain in the OFF position.

2. The machine harness remains disconnected from the ECM and the switch.

3. At the harness connector for the switch, connect a jumper wire between contact 4 (wire D756-YL) and contact 2 (wire D735-PK).

4. At the harness connector for the ECM, measure the resistance from contact J1-37 (wire D735-PK) to contact J1-39 (wire D756-YL).

Expected Result:

The resistance is less than 5 ohms.

Results:

• OK - The resistance is less than 5 ohms. Proceed to Test Step 6.

• NOT OK - The resistance is greater than 5 ohms. The circuit is open.

  Repair: The machine harness has failed. Repair the machine harness or replace the machine harness.

  STOP

Test Step 6. CHECK IF THE DIAGNOSTIC CODE REMAINS

1. Inspect the contacts of the harness connectors and clean the connectors.

2. Reconnect all harness connectors.

3. Turn the battery disconnect switch and the key start switch to the ON position.

4. Operate the machine.

5. 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: The ECM may have failed, but is unlikely. 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 (Power Train) - 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 when disconnected and reconnected. Resume normal machine operation.

  STOP