MBE 900 4000 Troubleshooting – Section 15.2 Troubleshooting PID 174

Section 15.2
Troubleshooting PID 174

The following will troubleshoot PID 174. See Figure "Location of Supply Fuel Temperature Sensor" for SFT sensor location.‪

1. SFT Sensor‪

‪

Figure 1. Location of Supply Fuel Temperature Sensor

Section 15.2.1
174 03 – Supply Fuel Temperature Sensor Open Circuit

Perform the following steps to troubleshoot an SFT sensor open circuit fault:‪

1. If faults 174 03 and 175 03 are active at the same time, refer to "16.2.1 175 03 – Engine Oil Temperature Open Circuit" .
2. If faults 174 03 and 175 03 are not active at the same time, go to step 3 .
3. Bridge pins 1 and 2 of the SFT sensor.
   1. If fault 174 04 is the only active fault after bridging pins, replace SFT sensor. Erase fault code memory.
   2. If fault 174 04 is not the only active fault after bridging pins, go to step 4 .
4. Bridge pin 1 of the SFT sensor connector to ground. See Figure "Supply Fuel Temperature Sensor Connector" .
   

   1. Pin 1‪	3. SFT Sensor Connector‪
   2. Pin 2‪	‪

   Figure 2. Supply Fuel Temperature Sensor Connector

   1. If fault 174 04 is not active after bridging pin 1 to ground, refer to "15.2.1.1 Required Action" .
   2. If fault 174 04 is active after bridging pin 1 to ground, go to step 5 .
5. Measure the resistance in 55-pin connector wire 4 to pin 2 of the SFT sensor connector. See Figure "Supply Fuel Temperature Sensor Pins and 55-Pin Connector Wires" .
   

   Figure 3. Supply Fuel Temperature Sensor Pins and 55-Pin Connector Wires

   1. If resistance is less than 3 Ω, refer to "15.2.1.2 Required Action" .
   2. If resistance is more than 3 Ω, refer to "15.2.1.3 Required Action" .

Section 15.2.1.1
Required Action

Perform the following steps to resolve an SFT sensor open circuit fault:‪

1. Repair or replace open circuit in wire between pin 36 of the 55-pin connector and pin 1 of the SFT sensor. See Figure "55-Pin Engine Wiring Harness Connector" .
   

   1. 55-Pin Harness Connector‪

   ‪

   Figure 4. 55-Pin Engine Wiring Harness Connector

2. Erase fault code memory.

Section 15.2.1.2
Required Action

Perform the following steps to resolve an SFT sensor open circuit fault:‪

1. Check all contacts and connections.
2. Contact Detroit Diesel Technical Service for authorization to replace the PLD-MR. Set parameters on new PLD-MR.
3. Erase fault code memory.

Section 15.2.1.3
Required Action

Perform the following steps to resolve an SFT sensor open circuit fault:‪

1. Repair open circuit in 55-pin connector wire 4 to pin 2 of the SFT sensor connector. See Figure "Supply Fuel Temperature Sensor Pins and 55-Pin Connector Wires" .
2. Erase fault code memory.

Section 15.2.2
174 04 – Supply Fuel Temperature Sensor Short to Ground

Perform the following steps to troubleshoot an SFT sensor short-to-ground fault.‪

1. Unplug the SFT sensor connector.
   1. If new fault 174 03 is active after the connector is unplugged, refer to "15.2.2.1 Required Action" .
   2. If new fault 174 03 is not active after the connector is unplugged, go to step 2 .
2. Check the resistance between pin 1 of the SFT sensor and ground.
   1. If resistance is less than 30 Ω, refer to "15.2.2.2 Required Action" .
   2. If resistance is greater than 30 Ω, refer to "15.2.2.3 Required Action" .

Section 15.2.2.1
Required Action

Perform the following steps to resolve an SFT sensor short-to-ground fault.‪

1. Remove and replace SFT sensor.
2. Erase fault code memory.

Section 15.2.2.2
Required Action

Perform the following steps to resolve an SFT sensor short-to-ground fault.‪

1. Repair short to ground in 55-pin connector wire 36 to pin 1 of the SFT sensor connector.
2. Erase fault code memory.

Section 15.2.2.3
Required Action

Perform the following steps to resolve an SFT sensor short-to-ground fault.‪

1. Clean and check the SFT sensor contacts.
2. If fault 174 03 is active after cleaning and checking the contacts, perform the following steps:
   1. Contact Detroit Diesel Technical Service for authorization to replace the PLD-MR. Set parameters on new PLD-MR.
   2. Erase fault code memory.