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

Instrumentation, Message Center and Warning Chimes

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

Normal Operation

The PCM continuously monitors the fuel level and retains the last updated value prior to the ignition switch being placed in the OFF position. After the ignition switch is placed in the ON position a new fuel level is taken and compared to the level recorded at ignition off. If the fuel level has increased, a flag sets in the PCM indicating the vehicle was refueled. If the Evaporative Emission (EVAP) monitor detects a gross leak while the refueling flag is set, a loose fuel filler cap or an incorrectly sealed fuel tank filler pipe (if equipped) is suspected and the PCM sets DTC P0457. When the PCM sets the DTC, the PCM sends the Instrument Panel Cluster (IPC) a check fuel cap message center indicator on request.

If the check fuel cap request is missing for less than 5 seconds, the check fuel cap message center indicator remains in the last indication state (on or off), based upon the last known message received. If the check fuel cap request is missing for more than 5 seconds or more, the IPC (Instrument Panel Cluster) sets DTC U0100:00 in continuous memory and defaults the check fuel cap message center indicator inactive (off).

NOTE: If DTC U0100:00 sets in the IPC (Instrument Panel Cluster), other observable symptoms may be an inoperative speedometer, tachometer or odometer.

This pinpoint test is intended to diagnose the following:

- Message center concern

- Evaporative emission system concern

- PCM

- IPC (Instrument Panel Cluster)

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

AM1 VERIFY THE OPERATION OF THE DOOR AJAR MESSAGE CENTER WARNING INDICATOR

- Close all doors then open the LH front door.

- Ignition ON.

- NOTE: If multiple warnings are present, the message center cycles through each of the warning indicators. Allow the displays to cycle through each display while determining whether the door ajar message center warning indicator is active.
Observe the message center.


Is the door ajar message center telltale warning indicator active?

Yes
GO to AM2.

No
GO to Pinpoint Test AN. Pinpoint Test AN: The Door Ajar Message Center Warning Indicator Is Never/Always On

AM2 RETRIEVE THE RECORDED DTCs FROM THE PCM KOEO (Key ON Engine OFF) SELF-TEST

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

Is PCM DTC P0457 recorded?

Yes
If the check fuel cap message center indicator is always on, REFER to Computers and Control Systems Information.

If the check fuel cap message center indicator is never on, GO to AM3.

No
If the check fuel cap message center indicator is always on, INSTALL a new IPC (Instrument Panel Cluster). REFER to Instrument Panel Cluster (IPC) . TEST the system for normal operation.

If the check fuel cap message center indicator is never on, the system is operating normally at this time. If the fuel cap was left off and the check fuel cap message center indicator did not turn on, driving conditions may not have allowed for the PCM to confirm an EVAP (Evaporative Emission) leak and message the IPC (Instrument Panel Cluster) to turn on the check fuel cap message center indicator.

AM3 RETRIEVE THE RECORDED DTCs FROM THE IPC (Instrument Panel Cluster) SELF-TEST

- Check for recorded IPC (Instrument Panel Cluster) DTCs from the self-test.

Is DTC U0100:00 recorded?

Yes
GO to Pinpoint Test BA. Pinpoint Test BA: DTC U0100:00
No
INSTALL a new PCM. TEST the system for normal operation.