My speedometer does not display correct speed

The instrument cluster receives the vehicle speed sensor (VSS) signal which originates in the ABS module and is transmitted to the PCM over the communication network. The PCM monitors the VSS input and sends it to the instrument cluster over the communication network. With the VSS input, the instrument cluster provides the speedometer with a corresponding pointer movement.

• The speedometer/odometer is inoperative

• Powertrain control module (PCM)
• Instrument cluster

• Go To Pinpoint Test F .

Pinpoint Test F: The Speedometer/Odometer Is Inoperative
Normal Operation Vehicle speed information is sent to the powertrain control module (PCM) from the anti-lock brake system (ABS) module. The instrument cluster receives the vehicle speed data from the PCM over the communication network.

Possible Causes
• PCM
• instrument cluster

PINPOINT TEST F: THE SPEEDOMETER/ODOMETER IS INOPERATIVE Your best bet ,have the vehicle hooked to a professional scan tool an checked for DTC'S - diagnostic trouble code's , before you replace parts that are not needed.
Test Step Result / Action to Take F1 RETRIEVE THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCs) FROM BOTH THE CONTINUOUS AND ON-DEMAND PCM SELF-TESTS

• Check for the recorded PCM DTCs from the continuous and on-demand self-tests.
• Are any PCM DTCs recorded?

Yes
REFER to the Powertrain Control/Emissions Diagnosis (PC/ED) manual to continue diagnosis of the DTCs.

No
For an inoperative speedometer, GO to F2 .

For an inoperative odometer, GO to F3 . F2 CARRY OUT THE INSTRUMENT CLUSTER SPEEDOMETER GAUGE ACTIVE COMMAND USING THE DIAGNOSTIC TOOL

• Key in ON position.
• Enter the following diagnostic mode on the diagnostic tool: Instrument Cluster Active Command.
• Select the instrument cluster speedometer gauge active command. Trigger the active command on. Observe the speedometer gauge. The speedometer gauge should start 16 km/h (10 mph) and move to 194 km/h (120 mph).
• Is the speedometer gauge within specifications?

Yes
GO to F4 .

No
GO to F5 . F3 MONITOR THE INTEGRATED CIRCUIT DISPLAYS

• Key in ON position.
• Monitor the compass, air temperature and message center functions of the integrated circuit display.
• Do the compass, air temperature, or message center displays operate correctly?

Yes
GO to F5 .

No
Go To Pinpoint Test U to continue diagnosis of the integrated circuit display. F4 CHECK FOR CORRECT PCM OPERATION

• Disconnect all the PCM connectors.
• Check for:
  • corrosion
  • pushed-out pins
• Connect all the PCM connectors and make sure they seat correctly.
• Operate the system and verify the concern is still present.
• Is the concern still present?

Yes
INSTALL a new PCM. REFER to Section 303-14 . TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. F5 CHECK FOR CORRECT INSTRUMENT CLUSTER OPERATION

• Disconnect all the instrument cluster connectors.
• Check for:
  • corrosion
  • pushed-out pins
• Connect all the instrument cluster connectors and make sure they seat correctly.
• Operate the system and verify the concern is still present.
• Is the concern still present?

Yes
INSTALL a new instrument cluster. REFER to Instrument Cluster in this section. TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.

Speedometer
The instrument panel cluster (IPC) displays the vehicle speed based on the information from the body control module (BCM). The engine control module (ECM) calculates the vehicle speed based on the controller area network (CAN) serial data message indicating the wheel reference speed from the electronic brake control module (EBCM). The ECM sends a CAN serial data message to the BCM indicating the vehicle speed. The BCM sends a class 2 message to the IPC indicating the vehicle speed.
The speedometer defaults to 0 km/h (0 mph) when any of the following occur:
• The EBCM detects a malfunction in the vehicle speed sensor circuit.
• The ECM detects a loss of CAN communications with the EBCM.
• The BCM detects a loss of CAN communications with the ECM.
• The IPC detects a loss of class 2 communications with the BCM.

Having the vehicle scanned for codes would probably point you in a correct diagnostic direction .

cant

Why ? speedometer not working ? Does the vehicle shift correctly ? The VSS - vehicle speed sensor is an input to the PCM - engine computer > Speed info is sent from the PCM to the microprocessor in the instrument cluster over the class 2 serial data bus . 2003 - 2006 GM vehicles had bad step motors in the instrument cluster . Step motors control gauge position. The VSS is located on the transmission case Vehicle Speed Sensor (VSS)
Lower right rear of the engine compartment, mounted to the right side of the transaxle.

Speedometer
The instrument panel cluster (IPC) displays the vehicle speed as determined by the powertrain control module (PCM). The PCM converts the data from the vehicle speed sensor to a 4000 pulses/mile signal. The IPC uses the vehicle speed signal circuit (4000 pulses/mile), class 2 message from the PCM in order to calculate the vehicle speed. If the IPC detects a malfunction in the vehicle speed signal circuit from the PCM, the IPC uses the class 2 message from the EBCM, indicating the vehicle speed as a backup. If the speedometer reaches (108 mph) the fuel with shut-off, and it will turn back ON when the speedometer is at (106 mph). The speedometer displays either miles or kilometers as requested by the activation of the English/metric button on the driver information center (DIC). The associated indicator (km/h or mph) illuminates.

The speedometer provides speed information based on a speed/distance pulse signal from the vehicle speed sensor (VSS). The VSS is mounted on the speedometer driven gear in the transmission.
or the gauge is bad .

• The speedometer/odometer is inoperative

• CJB fuse 14 (10A).
• Vehicle speed sensor (VSS).
• Circuitry.
• Instrument cluster.

• Go To Pinpoint Test E .

PINPOINT TEST E: THE SPEEDOMETER/ODOMETER IS INOPERATIVE CAUTION: Use the correct probe adaptor(s) when making measurements. Failure to use the correct probe adaptor(s) may damage the connector.
CONDITIONS DETAILS/RESULTS/ACTIONS E1 CHECK VSS SPEED SIGNAL BETWEEN CIRCUITS 679 (GY/BK) AND CIRCUIT 676 (PK/OG)
VSS C1088
Raise the drive wheels off the ground. While rotating the driveshaft, measure the AC voltage between the VSS C1088 pin 1, circuit 679 (GY/BK), component side and the VSS C1088 pin 2, circuit 676 (PK/OG), component side.

• Is the voltage between 1.3 volts AC to 6.1 volts AC?

Yes GO to E2 .

No CHECK and INSPECT the speedometer drive gear. INSTALL a new VSS if the speedometer drive gear is OK. TEST the system for normal operation E2 CHECK CIRCUIT 679 (GY/BK) AND CIRCUIT 676 (PK/OG) BETWEEN THE INSTRUMENT CLUSTER AND THE VSS

Well Cliff your really going to have to take this to a professional shop or Ford dealer ! You don't want to just replace parts on this , could get very expensive ! I don't know how familiar you are with newer vehicles , given the all the electronic modules on vehicles today. There is a serial data communication network called CAN .controller area network that the modules share info on. Your instrument cluster is a module of a kind too , has microprocessor it side ! You really need a dealership type scan tool to check this one out. You could possibly need a new instrument cluster or a PCM ! Then there would need to be programmed ! this is nothing for a do it yourselfer to do !
Speedometer
The instrument cluster receives the vehicle speed sensor (VSS) signal from the powertrain control module (PCM) over the high speed controller area network (HS-CAN). The instrument cluster monitors the VSS input from the PCM and commands the speedometer with a corresponding movement of the pointer.

• The speedometer/odometer is inoperative

• PCM
• Instrument cluster

• Go To Pinpoint Test E .

Pinpoint Test E: The Speedometer/Odometer Is Inoperative
Normal Operation The instrument cluster receives the vehicle speed sensor (VSS) signal from the powertrain control module (PCM) over the high speed controller area network (HS-CAN). The instrument cluster monitors the VSS input from the PCM and commands the speedometer with a corresponding movement of the pointer.

Possible Causes
• PCM
• Instrument cluster

PINPOINT TEST E: THE SPEEDOMETER/ODOMETER IS INOPERATIVE Test Step Result / Action to Take E1 RETRIEVE THE RECORDED DTCs FROM BOTH THE CONTINUOUS AND ON-DEMAND PCM SELF-TESTS

• Check for recorded PCM DTCs from the continuous and on-demand self-tests.
• Are any PCM DTCs recorded?

Yes
REFER to the Powertrain Control/Emissions Diagnosis (PC/ED) manual.

No
GO to E2 . E2 CARRY OUT THE INSTRUMENT CLUSTER SPEEDOMETER OUTPUT STATE CONTROL USING THE SCAN TOOL

• Key in ON position.
• Enter the following diagnostic mode on the diagnostic tool: Instrument Cluster Output State Control.
• Enter the instrument cluster output state control and select SPDOMETER. Command the speedometer on and off. Observe the speedometer.
• Does the speedometer start at 0 and move to 193 km/h (120 mph) when commanded on, and return to 0 when commanded off?

Yes
GO to E3 .

No
GO to E4 . E3 MONITOR THE DISPLAY SEGMENT CONTROL DISPLAY

• Observe the odometer in the message center (message center cluster) or integrated circuit (base cluster) display area.
• Does the odometer display all dashes (-----)?

Yes
GO to E5 .

No
If the message center (message center cluster) or integrated circuit (base cluster) display is blank, GO to E4 . E4 CHECK FOR CORRECT INSTRUMENT CLUSTER OPERATION

• Disconnect the instrument cluster connector.
• Check for:
  • corrosion
  • damaged pins
  • pushed-out pins
• Connect the instrument cluster connector and make sure it seats correctly.
• Operate the system and verify the concern is still present.
• Is the concern still present?

Yes
INSTALL a new instrument cluster. REFER to Instrument Cluster in this section. TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. E5 CHECK FOR CORRECT PCM OPERATION

• Disconnect all the PCM connectors.
• Check for:
  • corrosion
  • damaged pins
  • pushed-out pins
• Connect all the PCM connectors and make sure they seat correctly.
• Operate the system and verify the concern is still present.
• Is the concern still present?

Yes
INSTALL a new PCM. REFER to Section 303-14 . TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. Good luck !

Speedometer The instrument cluster receives the vehicle speed sensor (VSS) signal from the powertrain control module (PCM) through the standard corporate protocol (SCP) communication network. The instrument cluster monitors the VSS input from the PCM and commands the speedometer with a corresponding movement of the pointer.

• The speedometer/odometer is inoperative

• Circuitry.
• Powertrain control module (PCM).
• Instrument cluster.

• Go To Pinpoint Test L .

PINPOINT TEST L: THE SPEEDOMETER/ODOMETER IS INOPERATIVE Test Step Result / Action to Take L1 RETRIEVE THE RECORDED DTCS FROM BOTH CONTINUOUS AND ON-DEMAND INSTRUMENT CLUSTER SELF-TESTS

• Use the recorded instrument cluster DTCs from the continuous and on-demand self-tests.
• Are any instrument cluster DTCs recorded?

Yes
If instrument cluster U1123 is retrieved, REFER to Powertrain Control/Emissions Diagnosis (PC/ED) manual to continue diagnosis.

For all other instrument cluster DTCs, REFER to the Instrument Cluster Diagnostic Trouble Code (DTC) Index.

No
For inoperative speedometer, GO to L2 .

For inoperative odometer, GO to L3 . L2 CARRY OUT THE SPEEDOMETER ACTIVE COMMAND USING THE DIAGNOSTIC TOOL

• Connect the diagnostic tool.
• Key in ON position.
• Enter the following diagnostic mode on the diagnostic tool: Instrument Cluster Active Command.
• Select the instrument cluster speedometer active command.
• Trigger the speedometer and scroll in increments of 10% while monitoring the speedometer. The speedometer should increase in increments of approximately 20 km/h (12 mph) for each 10% change.
• Does the speedometer increase within specifications?

Yes
REFER to Powertrain Control/Emissions Diagnosis (PC/ED) manual to continue diagnosis.

No
GO to L4 . L3 MONITOR THE INTEGRATED CIRCUIT DISPLAYS

• Key in ON position.
• Monitor the compass, air temperature and message center functions of the integrated circuit display.
• Do the compass, air temperature or message center displays operate correctly?

Yes
GO to L4 .

No
Go To Pinpoint Test AE . L4 CHECK FOR CORRECT INSTRUMENT CLUSTER OPERATION

• Disconnect all instrument cluster connectors.
• Check for:
  • corrosion
  • pushed-out pins
• Connect all instrument cluster connectors and make sure they seat correctly.
• Operate the system and verify the concern is still present.
• Is the concern still present?

Yes
INSTALL a new instrument cluster. REFER to Instrument Cluster in this section. TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. There isn't a fuse just for the speedometer , there are four fuse for the whole instrument cluster . If one of these fuse's were burnt you would have more then just the speedometer not working ! You need to have a scan tool to find out what is up ! you could need a new cluster ! Is the check engine light on ? if not wouldn't think vehicle speed sensor bad , besides speed info for speedometer PCM uses for transmission shift points ! Good luck ,hope this helps !

First check the code what is then try to fix.Could be speed sensor.

replace the VSS as it controls the shifting and the speedo operation

Your vehicle does not have a traditional speedometer cable. Instead it uses a VSS (Vehicle Speed Sensor) to read speed of the vehicle below is a short test to help you determine if it is the VSS that has failed.

SPEEDOMETER VEHICLE SPEED SENSOR TEST

1. Press and release trip odometer button until function number 6 appears in display window.

2. Turn a front wheel and observe display (pulses are added to number in display. Check impulse signal for speedometer vehicle speed sensor. If 7 pulses are generated per wheel revolution, vehicle speed sensor is okay.

3. If specified number of pulses are not generated, check for open in wiring harness between speed sensor and instrument cluster. Repair wiring harness if necessary. If wiring harness is okay, replace speedometer vehicle speed sensor.