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 +2.05 kPa (0.3 psi) (signal high) or below -3.10 kPa (-0.45 psi) (signal low).
Diagnostic trouble code (DTC) EFI-621 is stored if the signal is unstable (signal sporadic) for 25 seconds.

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 accelerometer power cable
- short-circuit to ground in power cable
- contact resistance in terminals
- defective fuel tank pressure sensor
- defective air conditioning (A/C) pressure sensor
- defective atmospheric pressure sensor
- defective accelerometer

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

Fault symptom[s]
- none.