DD15 723/FMI 31 Troubleshooting

723/FMI 31

This fault indicates there is no match of camshaft and crankshaft signals.‪

1. Are there any other camshaft or crankshaft codes present?
   1. Yes, repair circuit failure. If the code is still active, go to next step.
   2. No, go to next step.
2. Has the engine had any gear train, camshaft, or flywheel repairs made?
   1. Yes, verify proper gear train timing and proper flywheel installation.
   2. No, inspect the tone wheel on the intake cam for damage. Check gear train for excessive lash or damage. If no concerns are found, go to next step.
3. Remove the Camshaft Position Sensor and inspect for damage. Is there damage to the sensor?
   1. Yes, replace the sensor. Refer to “73.5.1 Verify Repairs” .
   2. No, go to next step.
4. Remove the Crankshaft Position Sensor and inspect for damage. Is there damage to the sensor?
   1. Yes, replace the sensor. Refer to “73.5.1 Verify Repairs” .
   2. No, go to next step.
5. Check for loose debris in the flywheel housing, clutch damage, or metal debris in the oil. Repair as necessary. Refer to “73.5.1 Verify Repairs” .

Verify Repairs

Verify repairs as follows:‪

1. Turn ignition OFF.
2. Reconnect any electrical connections that were disconnected to perform the diagnosis.
3. Clear codes with DDDL 7.0 or latest version.
   

   ENGINE EXHAUST ‪
   To avoid injury from inhaling engine exhaust, always operate the engine in a well-ventilated area. Engine exhaust is toxic.‪

4. Start and bring engine up to operating temperature (over 140°F/60°C).
5. Verify operation is satisfactory and no warning lamps illuminate. If warning lamps illuminate, troubleshoot the codes.