DD15 Troubleshooting – Section 97.3 SPN 2791/FMI 5

Section 97.3
SPN 2791/FMI 5

This diagnostic condition is typically an open circuit fault.‪

Check as follows:‪

1. Check for multiple codes.
   1. If 2791/5, 27/4, and 1073/4 are present, repair the open between pin 62 of the 120–pin MCM connector and EGR valve and front Jake Brake solenoid. Refer to "97.3.1 Verify Repairs" .
   2. If only 2791/5 is present, go to the next step.
2. Disconnect the EGR valve.
3. Disconnect the 120–pin MCM connector.
4. Measure the resistance between pin 1 of the EGR valve harness connector and pin 61 of the 120–pin MCM connector.
   1. If the resistance is greater than 3 Ω, repair the open between pin 1 of the EGR valve harness connector and pin 61 of the 120–pin MCM connector. Refer to "97.3.1 Verify Repairs" .
   2. If the resistance is less than 3 Ω, replace the EGR valve. Refer to "97.3.1 Verify Repairs" .

Section 97.3.1
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. If assistance is required, call the Detroit Diesel Customer Support Center at 313–592–5800.