Test J: The Check Fuel Cap Warning Indicator Is Never/Always On

PINPOINT TEST J: THE CHECK FUEL CAP WARNING INDICATOR IS NEVER/ALWAYS ON

J1-J4:

Normal Operation
The powertrain control module (PCM) monitors the fuel tank evaporative emission system for significant leaks that occur following refueling of the vehicle. If the PCM detects that the fuel cap has been left off following vehicle refueling, the PCM sends a message to the instrument cluster over the communication network to turn on the check fuel cap warning indicator.

DTC P0457 - sets in the PCM if the PCM detects a fuel tank pressure change greater than -23.7 kPa (-7 in-Hg) of water within 30 seconds after refueling occurs, or if there is an excessive purge (fuel vapor) flow of greater than 0.45 gm/s (0.06 lb) per minute.

Possible Causes
- PCM
- Instrument cluster