MBE 4000 DDEC VI Troubleshooting – Section 35.2 SPN 175/FMI 3

Section 35.2
SPN 175/FMI 3

‪

This diagnosis is typically engine oil temperature short to power.‪

Section 35.2.1
Check for Short to Power

Check for a short to power as follows:‪

1. Check for multiple codes..
   1. If codes 100/3, 175/3 and 3480/3 are active at the same time, repair the open between pin 82 of the 120–pin MCM connector and associated sensors. Refer to "35.2.1.1 Verify Repairs" .
   2. If 100/3 and 175/3 are active, repair the open between pin 82 of the 120–pin MCM connector and pin 3 of the Engine Oil Temperature Sensor. Refer to "35.2.1.1 Verify Repairs" .
   3. If only fault 175/3 is active, go to step 2 .
2. Disconnect the Engine Oil Pressure/Temp Sensor.
3. Disconnect the 120–pin MCM connector.
4. Measure the resistance between pins 1 and 2 of the Engine Oil Pressure/Temp Sensor.
   1. If the resistance is greater than 130k Ω, replace the Engine Oil Pressure/Temp Sensor. Refer to "35.2.1.1 Verify Repairs" .
   2. If he resistance is less than 130k Ω, go to step 4 .
5. Turn the ignition ON (key ON, engine OFF).
6. Measure the voltage between pins 2 of the Engine Oil Pressure/Temp Sensor harness and ground.
   1. If the voltage is greater than 2.75 volts, go to step 7 .
   2. If the voltage is less than 2.75 volts, repair the open circuit between pin 108 of the 120–pin MCM connector and pin 2 of the Engine Oil Pressure/Temp Sensor. See Figure "Engine Oil Pressure/Temp Sensor Wiring" . Refer to "35.2.1.1 Verify Repairs" .
   

   Figure 1. Engine Oil Pressure/Temp Sensor Wiring

7. Turn the ignition OFF.
8. Disconnect the 120–pin MCM connector.
9. Measure the resistance between pins 1 and 2 of the Engine Oil Pressure/Temp Sensor harness connector.
   1. If the resistance is greater than 5Ω, repapir the short to power on the circuit between pin 108 of the 120–pin MCM connector and pin 2 of the Engine Oil Pressure/Temp Sensor harness connector. Refer to "35.2.1.1 Verify Repairs" .
   2. If he resistance is less than 5Ω, repair the short between wires 105 and 108 of the 120–pin MCM connector. Refer to "35.2.1.1 Verify Repairs" .

Section 35.2.1.1
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.