Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information

Condition




Diagnostic trouble code (DTC) ECM-4020 is stored if the transmission control module (TCM) receives a signal from the fuel tank pressure sensor which corresponds to a pressure higher than 20 hPa (0.29 psi) (high signal) or lower than -30 hPa (-0.44 psi) (low signal) and interprets it as a fault. Diagnostic trouble code (DTC) ECM-4020 is stored when the signal is higher than 10 hPa (0.145 psi9 directly after start-up with an engine coolant temperature (ECT) lower than 35°C (95°F) and it is interpreted by the control module as a fault (faulty signal).

Substitute value
leakage diagnostic is disabled

Possible source

Signal too high:
- short-circuit to supply voltage in the signal cable
- open-circuit in the signal cable
- open-circuit in the ground lead
- defective fuel tank pressure sensor

Signal too low:
- short-circuit to ground in the signal cable
- short-circuit to ground in power cable
- defective fuel tank pressure sensor

Faulty signal:
- contact resistance in terminals
- defective fuel tank pressure sensor

Fault symptom[s]
- none