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Pinpoint Test U: The Grade Assist Indicator Is Never/Always On




Instrumentation, Message Center and Warning Chimes

Pinpoint Test U: The Grade Assist Indicator Is Never/Always On (Non-Hybrid)

Normal Operation

The Instrument Cluster (IC) receives the grade assist signal from the PCM over the High Speed Controller Area Network (HS-CAN) communication bus. When the grade assist function is selected, the PCM sends a message to the IC (Instrument Cluster) to illuminate the grade assist indicator. If the message is missing or if the data is deemed invalid by the IC (Instrument Cluster) for more than 5 seconds, the IC (Instrument Cluster) sets DTC U0100 in continuous memory and defaults the grade assist indicator off.

NOTE: If DTC U0100 is set in the IC (Instrument Cluster), other observable symptoms may be an inoperative speedometer, tachometer or odometer.

This pinpoint test is intended to diagnose the following:

- Transaxle concern

- PCM

- IC (Instrument Cluster)

PINPOINT TEST U : THE GRADE ASSIST INDICATOR IS NEVER/ALWAYS ON (NON-HYBRID)

U1 CHECK THE OPERATION OF THE GRADE ASSIST FUNCTION

- Verify that the grade assist function turns on and off by pressing the grade assist button on and off while driving the vehicle.

Does the grade assist function operate correctly?

Yes
GO to U2.

No
REFER to Automatic Transmission/Transaxle.

U2 CARRY OUT THE IC (Instrument Cluster) INDICATOR LAMP CONTROL ACTIVE COMMAND USING THE SCAN TOOL

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: IC (Instrument Cluster) DataLogger.

- Select the IC (Instrument Cluster) grade assist indicator (OVERDRV) active command. Command the O/D (Overdrive) cancel/grade assist indicator on and off while observing the O/D (Overdrive) cancel/grade assist indicator.

Does the O/D (Overdrive) cancel/grade assist indicator illuminate when commanded on and turn off when commanded off?

Yes
GO to U3.

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

U3 RETRIEVE THE RECORDED DTCs FROM THE IC (Instrument Cluster) SELF-TEST

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

Are any DTCs recorded?

Yes
For DTC U0100, GO to Pinpoint Test AV Pinpoint Test AV: DTC U0100.

For all other DTCs, REFER to DTC Charts Instrumentation, Message Center and Warning Chimes.

No
GO to U4.

U4 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.

Are any PCM DTCs recorded?

Yes
REFER to Computers and Control Systems Information.

No
INSTALL a new PCM. TEST the system for normal operation.