Troubleshooting
Troubleshooting ECM-P009100
Checking fuel pressure sensor
Note! If diagnostic trouble codes (DTC) for the fuel pressure sensor or atmospheric pressure sensor are stored, troubleshooting of these diagnostic trouble codes shall be performed and remedied first.
Hint: The following method is for checking if the diagnostic trouble code has been caused by defective fuel pressure sensor. This can be done by comparing the readout signal from the fuel pressure sensor with actual fuel pressure (readout on pressure gauge connected to fuel system's lines). The method requires accurate calibration of the pressure gauge for measuring the fuel pressure.
- Connect pressure gauge: Fuel pressure gauge Fuel Pressure Gauge
Caution! The pressure in the fuel system can reach approximately 650 kPa when this diagnostic trouble code (DTC) is stored. Use an adapted manometer.
- Run the engine until it is warm and let it idle.
- A/C off.
Read off relative fuel pressure.
The relative fuel pressure is calculated from the fuel pressure sensor's and the atmospheric pressure sensor's signal (= absolute pressure minus atmospheric pressure).
Check that the value on the pressure gauge and the readout value are the same. Different values indicate malfunction in the circuit for the fuel pressure sensor.
Is the fuel pressure sensor OK?
Yes - Checking control of fuel pressure
No - Checking components and wiring
-------------------------------------------------
Checking control of fuel pressure
Caution! The pressure in the fuel system can reach approximately 650 kPa when this diagnostic trouble code (DTC) is stored. Use an adapted manometer.
Hint: The following method is for checking the fuel system's pressure by reading out fuel pressure and the fuel pump's working load. If pressure gauge for pressure up to 650 kPa is connected, the fuel pressure sensor can also be checked during the test.
- Disconnect the pressure gauge if it is not adapted for higher pressures than 650 kPa.
- Run the engine until it is warm and let it idle.
- A/C off.
- Read off fuel pressure and the fuel pump's working load.
- The upper digital display and the graphic display (red characters) show absolute fuel pressure, calculated from the fuel pressure sensor.
- The middle digital display (blue characters) shows the fuel pump's current working load to hold current fuel pressure. (Normal value 50% ±10%.)
- The lower digital display shows the relative fuel pressure (white characters), calculated from the fuel pressure sensor and the atmospheric pressure sensor (= absolute pressure minus atmospheric pressure). If a pressure gauge is connected during the test it shall show this pressure.
Check the value for fuel pressure together with the value for the fuel pump's working load. Requested pressure is 380 kPa at idle. Fuel pressure (relative) lower than 380 kPa together with high working load on the fuel pump indicates a malfunction of the pressure control.
Is the function OK?
Yes - Checking components
No - Checking components
-------------------------------------------------
Checking components
Hint: The malfunction may be intermittent or may be due to the system having low flow capacity.
Check that the fuel level in the tank is not too low (almost no fuel).
Check fuel lines between fuel pump and the injector's distribution pipes for leakage.
Check the fuel pressure sensor's connector for contact resistance and oxidation.
Check the fuel pump module's connector for contact resistance and oxidation.
Check fuel lines and fuel filter for clogging.
Try with a new fuel pump if no malfunction is found in the above troubleshooting.
Remedy as necessary.
Other information
- Connecting the breakout box, B8444S Connecting the Breakout Box
- Signal specification, engine control module (ECM), B8444S Signal Specification
- For replacing fuel pump: Level sensor, fuel tank, right-hand/fuel tank, replacing Level Sensor, Fuel Tank, Right-Hand/Fuel Tank, Replacing
- Fuel pump driver module Service and Repair
- Checking wiring and terminals Checking Wiring and Terminals
Select Continue
Continue - Fault-tracing information
-------------------------------------------------
Fault-tracing information
Information
Fault-tracing information
If the fault is intermittent, do not verify fault-tracing if the fault does not recur.
It is possible to view the information again, or leave fault-tracing for this diagnostic trouble code (DTC).
Do you want to view the information again?
Yes - Attempt New Test
No - Exit Fault-Tracing
------------------------
Attempt New Test - Checking fuel pressure sensor
-------------------------------------------------
Checking components and wiring
Check the fuel pressure sensor's connector for contact resistance and oxidation.
Try with a new fuel pressure sensor if no malfunction is found in the above troubleshooting.
Remedy as necessary.
Other information
- Connecting the breakout box, B8444S Connecting the Breakout Box
- Signal specification, engine control module (ECM), B8444S Signal Specification
- Fuel pressure and temperature sensor, replacing, B8444S, B6324S Service and Repair
- Checking wiring and terminals Checking Wiring and Terminals
Continue - Verification
-------------------------------------------------
Checking components
Check that the fuel level in the tank is not too low (almost no fuel).
Check the connectors between fuel pump module and the fuel pump for contact resistance and oxidation.
Check fuel lines and fuel filter for clogging.
If no malfunction is found in the above troubleshooting, try with a new fuel pump.
Hint: The diagnostic trouble code may also have been generated by a defective fuel pump module.
Remedy as necessary.
Other information
- For replacing fuel pump: Level sensor, fuel tank, right-hand/fuel tank, replacing Level Sensor, Fuel Tank, Right-Hand/Fuel Tank, Replacing
- Fuel pump driver module Service and Repair
- Checking wiring and terminals Checking Wiring and Terminals
Continue - Verification
-------------------------------------------------
Verification
Verification
Hint: After carrying out the repair, check that the fault has been remedied.
Caution! The pressure in the fuel injection system can reach approximately 650 kPa when this diagnostic trouble code (DTC) is stored. Use an adapted manometer.
- Connect pressure gauge: Fuel pressure gauge Fuel Pressure Gauge
- Run the engine until it is warm and let it idle.
- A/C off.
Read off relative fuel pressure.
The relative fuel pressure is calculated from the fuel pressure sensor's and the atmospheric pressure sensor's signal (= absolute pressure minus atmospheric pressure).
Check that the value on the pressure gauge and the readout value are the same. Different values indicate malfunction.
Is the function OK?
Yes - Troubleshooting procedure complete
No - Fault-tracing information
-------------------------------------------------
Verification
Verification
Hint: After carrying out the repair, check that the fault has been remedied.
- Ignition off
- Reinstall the connectors, components etc.
- Engine idling
- Read off the fuel pressure and the work load of the fuel pump.
- The upper digital display and the graphic display (red font color) indicate the absolute fuel pressure, calculated from the fuel pressure sensor
- The center digital display (blue font color) indicates the current work load required for the fuel pump (FP) to maintain the present fuel pressure. (Normal value 50% ± 10&%.)
- The lower digital display indicates the relative fuel pressure (white font color), calculated from the fuel pressure sensor and the atmospheric pressure sensor (= absolute pressure minus atmospheric pressure). If a manometer is connected during the test, it should indicate this pressure.
Check the fuel pressure value together with the value for the fuel pump work load. The requested pressure is 380 kPa at idle speed. A (relative) fuel pressure lower than 380 kPa together with a high fuel pump work load indicates a fault in pressure regulation.
Is the signal within its permitted range?
Yes - Troubleshooting procedure complete
No - Fault-tracing information
-------------------------------------------------
Fault-tracing information
Information
Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed.
Exit fault-tracing for this diagnostic trouble code (DTC) or make another attempt.
Do you want to exit fault-tracing?
Yes - Exit Fault-tracing
No - Attempt New Test
------------------------
Attempt New Test - Checking fuel pressure sensor
-------------------------------------------------