Illustration 1 | g00735793 |
Schematic of the rear retarder control solenoid |
This diagnostic code is associated with the rear retarder control solenoid. This diagnostic code is recorded when the Power Train/Chassis Electronic Control Module (ECM) reads the current of the solenoid as being below normal.
The possible causes are listed:
- There is an open in the circuit.
- The solenoid has failed.
- The ECM has 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 1608 FMI 05 is active before performing this procedure.
Note: Use the 146-4080 Digital Multimeter for the measurements in this procedure.
System Response:
The rear retarder control solenoid is always de-energized. The ECM will not be able to energize the rear retarder control solenoid. The Automatic Retarder Control (ARC) will continue to operate using the front retarder control solenoid. The ARC system will operate at a reduced level of performance.
Test Step 1. CHECK THE SOLENOID.
- Turn the battery disconnect switch and the key start switch to the ON position.
- Disconnect the machine harness from the solenoid.
- At the machine harness connector for the solenoid, place a jumper wire from contact 1 (wire K744-BU(Blue)) to contact 2 (wire E790-PK(Pink)).
- Observe the status of the diagnostic code.
Expected Result:
The diagnostic code is active. Then, the diagnostic code is not active as the jumper wire is installed and removed.
Results:
- YES - The circuit is correct. The solenoid has failed.
Repair: Repeat this test "CHECK THE SOLENOID" in order to verify that the solenoid has failed. Replace the solenoid.
STOP
- NO - The diagnostic code remains active. Proceed to Test Step 2.
Test Step 2. CHECK THE SOLENOID CIRCUIT FOR AN OPEN.
- Turn the key start switch and the battery disconnect switch to the OFF position.
- Disconnect the J2 machine harness connector from the ECM.
- At the machine harness connector for the solenoid, the jumper wire remains installed.
- At J2 machine harness connector, measure the resistance from contact J2-3 (wire E790-PK(Pink)) to J2-2 (wire K744-BU(Blue)).
Expected Result:
The resistance should be less than 5 ohms.
Results:
- YES - The resistance is less than 5 ohms. The machine harness is correct. Proceed to Test Step 3.
- NO - The resistance measurement is not correct. There is an open circuit in the machine harness.
Repair: The open is in (wire K744-BU(Blue)) for the solenoid signal or in (wire E790-PK(Pink)) of the machine harness. Repair the machine harness or replace the machine harness.
STOP
Test Step 3. 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 1608 FMI 05.
Expected Result:
The CID 1608 FMI 05 is active.
Results:
- YES - The CID 1608 FMI 05 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 1608 FMI 05 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