Section 5.11
PID 94, FMI 1, Flash Code 48, Fuel Pressure Low
The fuel pressure is low due to a faulty sensor connection, a faulty sensor, problem in the fuel system, a short or an open wire.
Section 5.11.1
Troubleshooting
Troubleshoot as follows:
- Check wire 905 (yellow, Fuel Pressure Sensor) cavity M-1 in the Engine Sensor Harness (ESH) 30–pin connector (see Figure
"Engine Sensor Harness 30–pin Connector"
). If there is a short or an open wire, repair or replace the wire(s), pins, and sockets.
Figure 1. Engine Sensor Harness 30–pin Connector
- If the code is still active, go to step .
- If the code is no longer active, refer to "5.11.2 Verification" .
- Check the Fuel Pressure Sensor (FPS) using the DDEC Sensor Tester J 37164 (see Figure
"DDEC Sensor Tester J 37164"
).
Figure 2. DDEC Sensor Tester J 37164
- Disconnect the sensor. On Series 60G and 50G engines with a high pressure fuel system, the FPS is installed in a tee at the inlet to the low pressure regulator (see Figure
"Fuel Pressure Sensor Location"
).
Figure 3. Fuel Pressure Sensor Location
- Disengage the locking tang on the three-wire connector. Grasp the body of the connector and gently pull it free of the FPS.
- Use the appropriate wrench on the hex end of the FPS to unscrew it from the inlet tee.
- Connect the sensor to the tester at the correct connector.
- Clip the power leads to the 12 volt power source.
- Plug in a volt OHM meter. The tester will power up the sensor.
- If the FPS needs to be replaced, refer to "5.11.1.1 Replacing the Fuel Pressure Sensor" .
- If the FPS does not need to be replaced, go to Step .
- Check the fuel system and fuel tanks and repair if necessary.
- If the code is still active, go to step .
- If the code is no longer active, refer to "5.11.2 Verification"
- Check wire 909 (light green, PWM No. 2 out) cavity Y-1 to see if there is a short to wire 416 (gray, sensor supply, 5VDC) cavity W-1 in the ESH 30–pin connector (see Figure
"Engine Sensor Harness 30–pin connector"
). If there is a short, repair or replace the wire(s), pins, and sockets.
Figure 4. Engine Sensor Harness 30–pin connector
- If the code is still active, go to step .
- If the code is no longer active, refer to "5.11.2 Verification" .
- Check pin E (PWM No. 2 out) in the PSV connector (see Figure
"PSV Connector"
). If there is a short, repair or replace the wire(s), pins, and sockets.
Figure 5. PSV Connector
- If the code is still active, go to step .
- If the code is no longer active, refer to "5.11.2 Verification" .
- Check wire 452 (black, engine sensor return) cavity Y-2 in the ESH 30–pin connector to see if it is open (see Figure
"Engine Sensor Harness 30–pin connector"
). Also check pin D (engine sensor return) in the throttle actuator connector (see Figure
"Throttle Actuator Connector"
). Repair or replace any open wires, pins, and sockets.
Figure 6. Throttle Actuator Connector
- If the code is still active, call Detroit Diesel Technical Service.
- If the code is no longer active, refer to "5.11.2 Verification"
Section 5.11.1.1
Replacing the Fuel Pressure Sensor
The FPS is non-servicable and should be replaced as a unit. No adjustment is required.
Replace the FPS as follows:
Note: The FPS is an electrical device. Use care on installation.
- On the replacement FPS, use Loctite® Pipe Sealant with Teflon, PT-7260, or equivalent on all but the first two threads of the FPS to prevent leaks.
- Screw FPS into the regulator inlet tee.
- Engage locking tang of the three wire connector to the FPS.
- Turn the ignition to the ON position. Observe the DDR for any diagnostic code(s).
- If PID 94, FMI 1, Flash Code 48 is still active, call Detroit Diesel Technical Service.
- If PID 94, FMI 1, Flash Code 48 is not active. Refer to "5.11.2 Verification" .
Section 5.11.2
Verification
Verify troubleshooting as follows:
- Check the DDR to see if PID 94, FMI 1, Flash Code 48 is still active.
- If the code is still active, go to step 2.
- If the code is not active, troubleshooting is complete.
- If the code is still active, call Detroit Diesel Technical Service.
Series 50G and 60G Troubleshooting Guide - 6SE482 |
Generated on 10-13-2008 |