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Pinpoint Test S: The Overdrive (O/D) Off Indicator Is Never/Always On




Instrumentation and Warning Chimes

Pinpoint Test

Pinpoint Test S: The Overdrive (O/D) Off Indicator Is Never/Always On

Normal Operation

The overdrive (O/D) off function is controlled by the O/D off switch located on the shifter assembly. When the transmission control switch is placed in the O/D OFF position, the O/D off switch provides voltage to the PCM. The PCM provides the O/D off status to the Instrument Cluster (IC) over the High Speed Controller Area Network (HS-CAN) communication bus. When the overdrive is turned off, the PCM sends a message to the IC to turn on the O/D off indicator. If an O/D fault condition is detected, the PCM sends a message to the IC to flash the O/D off indicator. If the O/D status message is missing for more than 5 seconds, the IC illuminates the O/D off indicator. The IC sets DTC U0100 in continuous memory if the PCM data is missing for more than 5 seconds or if invalid data is received and the IC turns on the O/D off indicator.

This pinpoint test is intended to diagnose the following:

- PCM
- IC



PINPOINT TEST S: THE OVERDRIVE (O/D) OFF INDICATOR IS NEVER/ALWAYS ON

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S1 CHECK THE OVERDRIVE OPERATION


- Check the operation of the transmission control switch.
- Does the transmission control switch operate correctly?

Yes
GO to S2.

No
REFER to Automatic Transmission/Transaxle.

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S2 RETRIEVE THE RECORDED DTCs FROM THE PCM KOEO SELF-TEST


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

Yes
REFER to Computers and Control Systems Information.

No
GO to S3.

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S3 RETRIEVE THE RECORDED DTCs FROM THE IC SELF-TEST


- Retrieve the recorded DTCs from the IC self-test.
- Is DTC U0100 retrieved?

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

No
GO to S4.

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S4 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 O/D off indicator (O_DOFFLMP) active command. Command the O/D off indicator active command on then off again. Observe the overdrive off warning indicator.
- Does the overdrive off warning indicator illuminate when commanded on and turn off when commanded off?

Yes
INSTALL a new PCM. REFER to Computers and Control Systems. TEST the system for normal operation.

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

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