Signal Too Low - Intermittent Fault

ECM-4020 FUEL TANK PRESSURE SENSOR
SIGNAL TOO LOW - INTERMITTENT FAULT

Checking wiring and connectors



Hint: This diagnostic trouble code (DTC) may also be caused by a clogged EVAP canister shut-off valve. If there are no electrical faults, a quick test of the fuel tank system can be carried out from vehicle communication.

Check the fuel tank pressure sensor connector for contact resistance and oxidation according to [1][2]Checking Wiring and Terminals. Intermittent Faults

Check the signal cable between engine control module (ECM) connector terminal #B31 (#B41) and fuel tank pressure sensor connector terminal #2 for an intermittent short-circuit to ground according to [1][2]Checking Wiring and Terminals. Intermittent Faults

Check the signal cable between engine control module (ECM) connector terminal #B10 (#B20) and fuel tank pressure sensor connector terminal #3 for an intermittent short-circuit to ground according to [1][2]Checking Wiring and Terminals. Intermittent Faults

Other information:
- For connection of engine control module (ECM) breakout box, Connecting the Breakout Box (ECM)
- To access/replace the fuel tank pressure sensor, Fuel Tank Pressure Sensor, Replacing
- Voltage supply for the fuel tank pressure sensor #3 is approximately 5V. #1 is ground and #2 is signal.
- For information about signals, Pinout Values and Diagnostic Parameters


Fault-tracing information
If the fault is intermittent, do not verify fault-tracing if the fault does not recur.