Pinpoint Test F: The Speedometer Is Inoperative
Instrumentation, Message Center and Warning Chimes
Pinpoint Tests
Pinpoint Test F: The Speedometer Is Inoperative
Normal Operation
The Instrument Cluster (IC) receives the vehicle speed data from the PCM over the High Speed Controller Area Network (HS-CAN) communication bus. The vehicle speed data originates with the Output Shaft Speed (OSS) sensor. The OSS sensor sends the output shaft speed data to the Transmission Control Module (TCM). The TCM provides the output shaft speed data to the PCM over the HS-CAN bus. The PCM uses the messaged OSS data along with the tire size and axle ratio configuration stored in the Vehicle Identification (VID) block to generate the vehicle speed data sent to the IC. The IC monitors the vehicle speed data input from the PCM and commands the speedometer with a corresponding movement of the pointer.
If the OSS message is missing or if the OSS sensor fails, the PCM uses a vehicle speed input from the ABS module over the HS-CAN bus combined with the tire size and axle ratio configuration in the VID block to generate the vehicle speed data sent to the IC.
If the OSS message is missing or if the OSS sensor fails and the ABS vehicle speed message is missing, the IC defaults the speedometer to 0 rpm.
If the vehicle speed message is missing or deemed invalid for greater than 5 seconds, the IC sets DTC U0100 and defaults the speedometer to 0 rpm.
This pinpoint test is intended to diagnose the following:
- PCM
- IC
PINPOINT TEST F: THE SPEEDOMETER IS INOPERATIVE
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F1 RETRIEVE THE RECORDED DTCs FROM THE PCM KOEO SELF-TEST
- Check the recorded PCM DTCs from the Key ON Engine OFF (KOEO) self-test.
- Are any DTCs recorded?
Yes
DIAGNOSE all PCM DTCs first. REFER to Computers and Control Systems.
No
GO to F2.
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F2 CARRY OUT THE IC SPEEDOMETER ACTIVE COMMAND USING THE SCAN TOOL
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: IC DataLogger .
- Select the IC speedometer (SPD_IND) active command and sweep the gauge in 10% increments.
- Does the speedometer start at 0 km/h (0 mph) and increase by 19.3 km/h (12 mph) for each 10% increase commanded?
Yes
GO to F3.
No
INSTALL a new IC. REFER to Instrument Cluster (IC) Instrument Cluster (IC). TEST the system for normal operation.
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F3 RETRIEVE THE RECORDED DTCs FROM THE ABS MODULE SELF-TEST
- Check the recorded ABS module DTCs from the self-test.
- Are any DTCs recorded?
Yes
DIAGNOSE all ABS module DTCs first. REFER to Vehicle Dynamic Systems Testing and Inspection.
No
GO to F4.
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F4 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 AT. Pinpoint Test AT: DTC U0100
No
INSTALL a new PCM. REFER to Electronic Engine Controls Service and Repair. TEST the system for normal operation.
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