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Speedometer and/or Odometer Malfunction




Speedometer and/or Odometer Malfunction

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit/System Description

The instrument cluster displays the engine coolant temperature, fuel level, vehicle speed and the engine speed based on the information from the engine control module (ECM). The ECM sends information via a High Speed CAN-Bus signal to the body control module (BCM). The BCM then sends the information via a Low Speed CAN-Bus signal to the instrument cluster to display the engine coolant temperature, fuel level, the engine speed, the vehicle speed and the distance travelled, either in kilometers or miles, based on the vehicle requirements. The instrument cluster will display dashes when its VIN does not match the VIN received from the BCM.

Diagnostic Aids

If the VIN mismatch is corrected the odometer will once again be displayed in the instrument cluster. If the vehicle is driven for a calibrated distance with a VIN mismatch, it will cause the instrument cluster odometer to enter into an error mode and lock itself. When this occurs the dashes will remain on the display even after correcting the VIN mismatch. The vehicle odometer status data display on the scan tool can be used to identify a locked odometer. The only way to unlock the instrument cluster (clear the dashes from the display) is to perform an SPS programming event. Failure to follow the diagnostic and programming procedures may result in either an improper odometer value or a module replacement.

Reference Information

Schematic Reference

Instrument Cluster Schematics Instrument Cluster Schematics

Connector End View Reference

Component Connector End Views Sunshade - Left (D61)

Description and Operation

Instrument Cluster Description and Operation Instrument Cluster

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Control Module References for scan tool information

Circuit/System Verification

1. Verify no DTC is set.

If any DTC is set
Diagnose DTCs first. Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.

If no DTCs are set

2. Ignition ON, perform the Speedometer Sweep Test with the scan tool, verify the speedometer sweeps from low to high position.

If speedometer does not sweep
Replace the P16 Instrument Cluster.

If speedometer sweeps properly

3. Drive the vehicle, verify the speedometer gauge value matches the Vehicle Speed parameter on the scan tool.

If the values do not match
Replace the P16 Instrument Cluster.

If the speedometer value matches the scan tool parameter

4. Drive the vehicle, verify the odometer display and the displayed distance counts up while driving.

If the odometer displays only "----" (dashes)
Refer to Circuit/System Testing.

If the odometer display does not count up
Replace the P16 Instrument Cluster.

If speedometer sweeps and displays the correct value, and the odometer display counts up

5. All OK.

Circuit/System Testing

Note: If there are multiple modules not original to the vehicle and are not new correctly configured service parts, SPS may not be able to proper read or recover the vehicle odometer value. Follow government rules and documentation (including vehicle identification) regarding inaccurate/unknown odometer values.

Perform circuit/system verification first.

Instrument Cluster is Showing "----" (Dashes)

Correcting VIN mismatch - odometer is still unlocked.

1. Verify the vehicle odometer status with a scan tool. The reading should be Unlocked.

If the reading is Locked
Refer to correcting VIN mismatch - odometer locked.

If the reading is Unlocked

2. Using the scan tool, verify the BCM VIN matches the vehicle VIN placard.

If the VIN does not match
Reprogram the BCM, then proceed to Step 3.

If the VIN matches

3. Using the scan tool, verify the instrument cluster VIN matches the vehicle VIN placard.

If the VIN does not match
Reprogram the instrument cluster. Then proceed with step 4.

If the VIN matches

4. Ignition ON, verify the instrument cluster is displaying the correct value.

If the instrument cluster is still displaying "----" (dashes)
Replace the P16 Instrument Cluster.

Instrument Cluster is Showing "----" (Dashes)

Correcting VIN mismatch - odometer is locked.

1. Verify the vehicle odometer status with a scan tool. The reading should be Unlocked.

If the reading is Unlocked
Refer to Correcting VIN mismatch - odometer unlocked.

If the reading is Locked

2. Using the scan tool, verify the instrument cluster VIN matches the vehicle's VIN placard.

If the VIN does not match
Reprogram the Instrument Cluster. Then proceed with step 3.

If the VIN matches

3. Perform the BCM setup procedure in SPS.

4. Ignition ON, verify the instrument cluster is displaying the correct value.

If the instrument cluster is still displaying "----" (dashes)
Replace the P16 Instrument Cluster.

If instrument cluster is displaying the correct value

5. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

Control Module References Control Module References for instrument cluster, BCM or ECM replacement, programming, and setup