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

Instrumentation, Message Center and Warning Chimes

Pinpoint Tests

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

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 off, the PCM sends a message to the IC to illuminate the grade assist indicator. If the grade assist message is missing for less than 5 seconds, the grade assist indicator remains in the last state (on or off) based upon the last good known message. If the grade assist on/off message is missing for more than 5 seconds, the IC sets DTC U0100 in continuous memory and defaults the grade assist indicator off.

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

This pinpoint test is intended to diagnose the following:

- Transaxle concern
- PCM
- IC



PINPOINT TEST Y: THE GRADE ASSIST INDICATOR IS NEVER/ALWAYS ON

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Y1 CHECK THE OPERATION OF THE GRADE ASSIST FUNCTION


- Verify that the grade assist function operates while pressing the grade assist button on and off.
- Does the O/D function correctly?

Yes
GO to Y2.

No
Refer to Automatic Transmission/Transaxle. Testing and Inspection

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Y2 CARRY OUT THE IC INDICATOR LAMP CONTROL ACTIVE COMMAND USING THE SCAN TOOL


- Ignition ON.
- Enter the following diagnostic mode on the scan tool: IC DataLogger.
- Select the IC grade assist indicator (OVERDRV) active command. Command the grade assist indicator on and off while observing the grade assist indicator.
- Does the grade assist indicator illuminate when commanded on, and turn off when commanded off?

Yes
GO to Y3.

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

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Y3 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 AM. Pinpoint Tests AM: DTC U0100

No
GO to Y4.

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Y4 RETRIEVE THE RECORDED DTCs FROM BOTH THE PCM KOEO SELF-TEST


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

Yes
REFER to Computers and Control Systems Information.

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

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