Pinpoint Tests AK: The Check Fuel Cap Message Center Indicator Is Never/Always On

Instrumentation, Message Center and Warning Chimes

Pinpoint Tests

Pinpoint Test AK: The Check Fuel Cap Message Center Indicator Is Never/Always On

Normal Operation

The PCM monitors the fuel tank evaporative emission system for significant leaks that occur following refueling of the vehicle. Once the PCM detects a fuel vapor leak, the PCM sends the Instrument Cluster (IC) a message over the communication network to turn on the check fuel cap message center indicator. DTC P0457 sets in the PCM following a successful cruise test, which is initiated when the vehicle is driven at a steady speed above 64 km/h (40 mph) for a duration of approximately 4-5 minutes. If the PCM is unable to successfully run the cruise test, the IC does not receive the check fuel cap message and the check fuel cap message center indicator remains off.

- DTC P0457 (Evaporative Emission System Leak Detected [fuel cap loose/off]) - sets in the PCM if a fuel tank pressure change greater than -23.7 kPa (-7 in-Hg) of vacuum within 30 seconds after refueling occurs, or there is an excessive purge (fuel vapor) flow of greater than 454 g (1.0 lb) per minute.

This pinpoint test is intended to diagnose the following:

- Evaporative emission system concern
- IC



PINPOINT TEST AK: THE CHECK FUEL CAP MESSAGE CENTER INDICATOR IS NEVER/ALWAYS ON

-------------------------------------------------
AK1 RETRIEVE THE RECORDED DTCs FROM THE PCM KOEO SELF-TEST


- Check for recorded PCM DTCs from the Key ON Engine OFF (KOEO) self-test.
- Is PCM DTC P0457 recorded?

Yes
REFER to Computers and Control Systems Information.

No
If the check fuel cap message center indicator is never on, GO to AK2.

If the check fuel cap message center indicator is always on, INSTALL a new IC. REFER to Instrument Cluster (IC) Instrument Cluster (IC).
TEST the system for normal operation.

-------------------------------------------------
AK2 RETRIEVE THE RECORDED DTCs FROM THE IC SELF-TEST


- Check for recorded IC DTCs from the self-test.
- Is DTC U0100 recorded?

Yes
GO to Pinpoint Test BD. Pinpoint Tests BD: DTC U0100

No
GO to AK3.

-------------------------------------------------
AK3 VERIFY THE OPERATION OF THE DOOR AJAR MESSAGE CENTER WARNING INDICATOR


- Open the LH front door.
- Ignition ON.
- NOTE: If multiple warnings are present, the message center indicators rotate through each of the warnings. Allow the displays to rotate through each display while determining whether the door ajar message center warning indicator is active.
- Observe the message center or integrated display area of the IC.
- Is the door ajar message center indicator active?

Yes
The system is operating normally at this time. If the fuel cap was left off and the check fuel cap warning indicator did not turn on, driving conditions may not have allowed for the PCM to run the cruise test and message the IC to turn on the check fuel cap warning indicator.

No
INSTALL a new IC. REFER to Instrument Cluster (IC) Instrument Cluster (IC). TEST the system for normal operation.

-------------------------------------------------