Series 60 DDEC V Troubleshooting – Section 35.2 Troubleshooting Flash Code 31, SID 51, 52/FMI 3, 4 | Detroit Diesel Engine Troubleshooting (2024)

Section 35.2
Troubleshooting Flash Code 31, SID 51, 52/FMI 3, 4

This diagnostic condition is typically: ‪

• Output circuit open (FMI 3)
• Output wire is shorted to ground (FMI 4)

The following procedure will troubleshoot Flash Code 31.‪

Section 35.2.1
Check Configuration

Perform the following steps to check configuration.‪

1. If the unit has engine brakes, refer to "35.2.2 Determine Failure Mode" .
2. If the unit does not have engine brakes, the ECM/ECU is configured for engine brakes and shouldn't be. Contact the Detroit Diesel Customer Support Center (313–592–5800) with the engine serial number to have the data changed. Reprogram the ECM/ECU after the change and verify. Refer to "35.2.6.1 Verify Repairs" .

Section 35.2.2
Determine Failure Mode

Perform the following steps to determine failure mode.‪

1. Turn vehicle ignition ON.
2. Plug the diagnostic tool.
3. Read SAE code (s 051 or s 052).
   1. If the reading is FMI 3, there is an open. Refer to "35.2.3 Check for Open" .
   2. If the reading is FMI 4, there is a short to ground. Refer to "35.2.6 Check for Short" .

Section 35.2.3
Check for Open

Perform the following steps to check for open.‪

1. Turn vehicle ignition OFF.
2. Disconnect the 10-pin connector pigtail from engine brake injector harness.
3. Disconnect the 68-pin Engine Harness connector.
4. Install a jumper wire between pins 9 and 10, ECM/ECU side of pigtail.
5. Measure resistance between E-48 and E-49 of the Engine Harness connector.
   1. If measured resistance is less than 50 Ω, refer to "35.2.4 Check for Open (Inside Valve Cover)" .
   2. If measured resistance is greater than 50 Ω, one or both wires are open. Repair open. Refer to "35.2.6.1 Verify Repairs" .

Section 35.2.4
Check for Open (Inside Valve Cover)

Perform the following steps to check for open wire in the inside valve cover.‪

1. Reconnect the Engine Harness connector. See Figure "Engine Brake Harness Schematic" .
2. Measure resistance between pin 9 and the engine block and between pin 10 and engine block and the brake harness connector (brake side).
   1. If measured resistance is greater than 50 Ω or open, an open exists in one of the wires where the check was made. Repair open or replace the injector harness. Refer to "35.2.6.1 Verify Repairs" .
   2. If measured resistance is less than 50 Ω, refer to "35.2.4 Check for Open (Inside Valve Cover)" .

   

   Figure 1. Engine Brake Harness Schematic

Section 35.2.5
Check for Cylinder Block Ground

Perform the following steps to check for cylinder block ground.‪

1. If the cylinder block is connected to the battery ground, .
2. If the cylinder block is not connected to the battery ground, install a ground strap from the cylinder block to the battery negative (-). Refer to "35.2.6.1 Verify Repairs" .
3. Check brake solenoids. Refer to OEM guidelines.
   1. If the solenoids are in good condition, contact Detroit Diesel Customer Support Center (313–592–5800).
   2. If the solenoids are damaged, repair or replace them. Refer to "35.2.6.1 Verify Repairs" .

Section 35.2.6
Check for Short

Perform the following steps to check for a short.‪

1. Turn vehicle ignition OFF.
2. Unplug the Engine Harness connector.
3. Measure resistance between E-48 and a battery ground, and E-48 and the engine block. Repeat this check between E-49 and battery ground, and E-49 and the engine block. See Figure "ECM/ECU Engine Harness Connector" .

   

   Figure 2. ECM/ECU Engine Harness Connector

   1. If resistance for all measurements is greater than 5 Ω or open, go to step 4 .
   2. If any measured resistance is less than 5 Ω, the wire where the measurement was read is shorted to ground or to the engine. Repair short or replace the wire. Refer to "35.2.6.1 Verify Repairs" .
4. Measure resistance between E-48 and E-49.
   1. If measured resistance is less than 10 Ω, the E-48 and E-49 wires are shorted to each other. Repair short. Refer to "35.2.6.1 Verify Repairs" .
   2. If measured resistance is greater than 10 Ω, go to step 5 .
5. Check brake solenoids. Refer to OEM guidelines.
   1. If the solenoids are in good condition, contact Detroit Diesel Customer Support Center (313–592–5800).
   2. If the solenoids are damaged, repair or replace them. Refer to "35.2.6.1 Verify Repairs" .

Section 35.2.6.1
Verify Repairs

‪

Perform the following steps to verify repairs.‪

1. Connect any connectors removed for troubleshooting.
2. Start, run the engine, and operate the engine brake.
   1. If no lights come on, and no codes are logged, the repairs are complete. No further troubleshooting is required.
   2. If Amber Warning Lamp displays with codes s 51/3, s 51/4, s 52/3, or s 51/4, review this section to find the error. Refer to "35.2.1 Check Configuration" .