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

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 PCM and if a leak is detected it signals a fault by sending a message to the instrument cluster (IC) over the high speed controller area network (HS-CAN) communication bus. The instrument cluster (IC) illuminates the check fuel cap warning indicator. The instrument cluster (IC) sets DTC U0100 in continuous memory if the fuel tank pressure status message is missing for more than 5 seconds and the instrument cluster (IC) turns off the check fuel cap indicator.

This pinpoint test is intended to diagnose the following:
- PCM
- Instrument cluster (IC)

W1-W4:

W5: