DD15 SPN 2791/FMI 15 Troubleshooting

SPN 2791/FMI 15

This fault typically results from high load operation in high ambients. No action is necessary (this is a “silent” fault, the fan will be turned on).‪

Note: This fault is a concern only if the fan on times are excessive but coolant temperatures are in the normal operating range.

Check as follows:‪

1. Check for multiple codes:
   1. If SPN 110/FMI 0 is also present, repair the cooling system first. Refer to “97.9.1 Verify Repairs” .
   2. If only SPN 2791/FMI 15 is present, go to the next step.
2. Visually inspect for signs of exhaust leak in the area of the actuator.
   1. If exhaust leaks are present, repair as necessary. Refer to “97.9.1 Verify Repairs” .
   2. If no exhaust leaks are present, go to the next step.
3. Remove and inspect the actuator cooler lines and fittings.
   1. If coolant lines or fittings are kinked or plugged, repair/replace the damaged component. Refer to “97.9.1 Verify Repairs” .
   2. If coolant lines are not damaged and problem still persists, contact the Detroit Diesel Customer Support Center at 313–592–5800.

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.