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| Illustration 1 | g01042834 |
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Schematic of the retarder lever switch | |
This diagnostic code is associated with the retarder lever switch. This diagnostic code is recorded when the Power Train/Chassis Electronic Control Module (ECM) reads the signal wire of the switch and the voltage is high.
The possible causes of this diagnostic code are listed here:
- A shorted harness
- An open supply circuit to the switch
- A failed switch
- An open circuit
- The ECM may have failed. This is unlikely.
Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear these diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 1227 FMI 03 is active before performing this procedure.
Note: Use the 146-4080 Digital Multimeter for the measurements in this procedure.
System Response:
The manual retarder does not activate. The switch will operate properly after the diagnostic code has been corrected.
Test Step 1. CHECK THE SUPPLY VOLTAGE AT THE SENSOR.
- Turn the battery disconnect switch and the key start switch to the ON position.
- Check the voltage at the machine harness connector of the sensor from contact A (switch supply) to contact B (ground). Do not disconnect the switch. Use the 7X-1710 Multimeter Probe to measure the voltage.
Note: Check that circuit breaker #12 is not open.
Expected Result:
The voltage should measure approximately +battery.
Results:
- OK - The voltage is approximately +battery. The voltage is correct. Proceed to Test Step 3.
- NOT OK - The voltage is not approximately +battery. There is an open in the machine harness or the ECM has failed. It is unlikely that the ECM has failed. Proceed to Test Step 2.
Test Step 2. CHECK FOR AN OPEN IN THE SUPPLY CIRCUIT.
- The key start switch and the battery disconnect switch remain in the ON position.
- Disconnect the switch from the machine harness.
- At the machine harness connector for the switch, measure the voltage from contact A (switch supply) to frame ground.
Expected Result:
The voltage measures approximately +battery.
Results:
- OK - The voltage measures approximately +battery. The return circuit is open. Proceed to Test Step 3.
- NOT OK - The voltage does not measure approximately +battery. The supply circuit is open.
Repair: Repair the machine harness or replace the machine harness.
STOP
Test Step 3. CHECK THE SIGNAL CIRCUIT.
- Turn the battery disconnect switch and the key start switch to the ON position.
- Disconnect the machine harness connector from the switch.
- At the machine harness connector for the switch, measure the voltage between contact C (signal) and contact B (ground).
Expected Result:
The voltage should measure approximately 5 DCV.
Results:
- OK - The voltage is approximately 5 DCV. The voltage is correct.
Repair: Replace the switch.
STOP
- NOT OK - The voltage is not approximately 5 DCV. The voltage is not correct. Proceed to Test Step 4.
Test Step 4. CHECK FOR AN OPEN SIGNAL CIRCUIT.
- Turn the key start switch and the battery disconnect switch to the OFF position.
- The switch remains disconnected from the machine harness.
- Disconnect the machine harness from the ECM.
- Place a jumper wire between contact C (signal) and contact B (ground) of the machine harness connector for the switch.
- At the machine harness connector of the ECM, measure the resistance between the signal contact and frame ground.
Expected Result:
The resistance measures less than 5 ohms.
Results:
- OK - The resistance measures less than 5 ohms. The circuit is correct. Proceed to Test Step 5.
- NOT OK - The resistance is greater than 5 ohms. The circuit is open.
Repair: Repair the machine harness or replace the machine harness.
STOP
Test Step 5. CHECK THE SIGNAL WIRE FOR SHORTS.
- The battery disconnect switch and the key start switch remain in the OFF position.
- The machine harness remains disconnected from the ECM.
- Remove the jumper wire from contact C and contact B on the machine harness connector for the switch.
- At the J2-23 machine harness connector for the ECM, measure the resistance from (wire 706-BR(Brown)) to all contacts that have +battery supply.
Expected Result:
Each measurement is greater than 5 ohms.
Results:
- OK - Each measurement is greater than 5 ohms. The ECM has failed. Proceed to Test Step 6.
- NOT OK - The resistance measured less than 5 ohms. There is a short in the machine harness.
Repair: Repair the machine harness or replace the machine harness.
STOP
Test Step 6. 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 1227 FMI 03.
Expected Result:
The CID 1227 FMI 03 is active.
Results:
- YES - The CID 1227 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 1227 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