Section 114.1
SPN 3597/FMI 3

This diagnosis is typically proportional valve bank 1 circuit failed low.‪

Section 114.1.1
Circuit Check

Check as follows:‪

1. Turn the ignition ON (key ON, engine OFF).
2. Monitor the active codes.
3. Disconnect the rear valve cover injector harness.
4. Does SPN 3597/FMI 3 become inactive?
   1. If yes, go to step 5 .
   2. If no, go to step 9 .
5. Reconnect the rear valve cover injector harness.
6. Remove the upper valve cover.
7. Disconnect the rear Jake Brake® solenoid.
8. Does SPN 3597/FMI 3 become inactive?
   1. If yes, replace the rear Jake Brake solenoid. Refer to "114.1.1.1 Verify Repairs" .
   2. If no, replace the injector wiring harness. Refer to "114.1.1.1 Verify Repairs" .
9. Disconnect the turbo actuator.
10. Does SPN 3597/FMI 3 become inactive?
    1. If yes, replace the turbo actuator. Refer to "114.1.1.1 Verify Repairs" .
    2. If no, go to step 11 .
11. Disconnect the fan control solenoid.
12. Does SPN 3597/FMI 3 become inactive?
    1. If yes, replace the fan control solenoid. Refer to "114.1.1.1 Verify Repairs" .
    2. If no, go to step 13 .
13. Turn the ignition OFF.
14. Disconnect the MCM 120–pin connector.
15. Measure the resistance between pin 91 of the MCM 120–pin connector and ground.
    1. If the resistance is less than 5 Ω, repair the short to ground between pin 91 of the MCM 120–pin connector and the rear injector valve cover connector, turbo actuator connector and or fan control solenoid. Refer to "114.1.1.1 Verify Repairs" .
    2. If the resistance is greater than 5 Ω, go to step 16 .
16. Measure the resistance between pin 93 of the MCM 120–pin connector and ground.
    1. If the resistance is less than 5 Ω, repair the short to ground between pin 93 of the MCM 120–pin connector and the rear injector valve cover connector, turbo actuator connector and or fan control solenoid. Refer to "114.1.1.1 Verify Repairs" .
    2. If the resistance is greater than 5 Ω, contact the Detroit Diesel Customer Support Center at 313–592–5800 for MCM replacement.

Section 114.1.1.1
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.
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.