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

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


W1-W4:






W5:






Normal Operation
The check fuel cap warning indicator is used to indicate significant leaks that exceed specifications in the fuel tank evaporative system following fuel system filling. The fuel tank pressure is monitored by the powertrain control module (PCM) and if a leak is detected it signals a fault by sending a message to the instrument cluster over the high speed controller area network (CAN) communication bus. The instrument cluster illuminates the check fuel cap warning indicator.

DTC U0294 - sets if the fuel tank pressure status message is missing for more than 5 seconds and the instrument cluster turns off the check fuel cap indicator.

Possible Causes
- PCM
- Instrument cluster