MBE 4000 DDEC VI Troubleshooting – Section 55.2 SPN 641/FMI 4

Section 55.2
SPN 641/FMI 4

This diagnosis is typically a short to ground.‪

Section 55.2.1
Short to Ground Check

Check for short as follows:‪

1. Disconnect the wastegate control actuator connector.
2. Disconnect the 120–pin MCM connector.
3. Measure the resistance between pins 1 and 3 of the wastegate control actuator connector. See Figure "Wastegate" .
   

   Figure 1. Wastegate

   1. If the resistance is less than 5 Ω, repair the short between pins 35 and 38 of the 120–pin MCM connector. Refer to "55.2.1.1 Verify Repairs" .
   2. If the resistance is greater than 5 Ω, go to step 4 .
4. Measure the resistance between pin 3 of the wastegate control actuator connector and ground.
   1. If the resistance is less than 5 Ω, repair the short between pin 3 of the wastegate control actuator connector and ground. Refer to "55.2.1.1 Verify Repairs" .
   2. If the resistance is greater than 5 Ω, replace the wastegate control actuator. Refer to "55.2.1.1 Verify Repairs" .

Section 55.2.1.1
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.