Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information EFI-621

Condition




Diagnostic trouble code (DTC) EFI-621 (Fuel tank pressure sensor, signal) is stored if the engine control module (ECM) receives a signal from the tank pressure sensor corresponding to a pressure above 2.95 kPa (signal high) or below -2.88 kPa (signal low).

Substitute value
- leakage diagnostic is disabled.

Possible source

Signal too high
- short-circuit to supply voltage in signal cable
- open-circuit in signal cable or ground lead
- contact resistance in terminals
- defective fuel tank pressure sensor.

Signal too low:
- short-circuit to ground in signal cable
- open-circuit in power cable
- short-circuit to ground in air conditioning (A/C) pressure sensor
- short-circuit to ground in atmospheric pressure sensor power cable
- short-circuit to ground in accelerometer power cable
- short-circuit to ground in power cable
- contact resistance in terminals
- defective air conditioning (A/C) pressure sensor
- defective atmospheric pressure sensor
- defective accelerometer
- defective fuel tank pressure sensor.

Signal sporadic:
- loose connections
- contact resistance in terminals
- defective atmospheric pressure sensor
- defective air conditioning (A/C) pressure sensor
- defective accelerometer
- defective fuel tank pressure sensor.

Fault symptom[s]
- none.