MBE 900 DDEC VI Troubleshooting – Section 68.2 SPN 709/FMI 4

Section 68.2
SPN 709/FMI 4

This fault code indicates that there is a short to ground.‪

Section 68.2.1
Short to Ground Check

Check as follows:‪

1. Put the ignition switch in the OFF position
2. Disconnect the fan control solenoid connector.
3. Disconnect the 120–pin MCM connector.
4. Measure the resistance between pin 1 of the fan control solenoid connector and ground.
   1. If the resistance is less than 5 Ω, repair the short to ground between pin 1 of the fan control solenoid connector and pin 98 of the 120–pin MCM connector. Refer to "68.2.1.1 Verify Repairs" .
   2. If the resistance is greater than 5 Ω, repair the short to ground between pin 2 of the fan control solenoid connector and pin 91 of the 120–pin MCM connector. Refer to "68.2.1.1 Verify Repairs" .

Section 68.2.1.1
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.