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Pinpoint Test H: The Speedometer Is Inoperative




Instrumentation, Message Center and Warning Chimes

Pinpoint Tests

Pinpoint Test H: The Speedometer Is Inoperative

Normal Operation

The PCM calculates the vehicle speed from the transaxle Output Shaft Speed (OSS) sensor input and from the tire size and axle ratio configuration in the PCM Vehicle Identification (VID) block. The PCM provides the Instrument Cluster (IC) with the vehicle speed data over the High Speed Controller Area Network (HS-CAN) bus. The IC monitors the vehicle speed input and commands the speedometer with a corresponding movement of the pointer.

If the IC does not receive the vehicle speed data from the PCM for 5 seconds or less, the IC defaults the speedometer to the last setting, based upon the last known good vehicle speed message. If the IC does not receive the vehicle speed data from the PCM for more than 5 seconds or if the data received is deemed invalid, the IC sets DTC U0100 in continuous memory and defaults the speedometer to 0 km/h (0 mph).

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

This pinpoint test is intended to diagnose the following:

- PCM
- IC



PINPOINT TEST H: THE SPEEDOMETER IS INOPERATIVE

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H1 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 (SPDOMETER) active command and command the speedometer on then off. Observe the speedometer. The speedometer starts at 0 km/h (0 mph) and moves to full stop, 193 km/h (120 mph) (Edge) or 225 km/h (140 mph) (MKX) and returns to 0 km/h (0 mph).
- Does the speedometer reading increase within the specifications?

Yes
GO to H2.

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

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H2 RETRIEVE THE RECORDED DTCs FROM THE PCM KOEO 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
GO to H3.

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H3 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 AU. Pinpoint Tests AU: DTC U0100

No
INSTALL a new PCM. REFER to Computers and Control Systems. TEST the system for normal operation.

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