GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2001 🢒 Yukon - 2WD 🢒 Body and Accessories 🢒 Instrument Panel, Gauges, and Console 🢒 Speedometer and/or Odometer Inaccurate or Inoperative

Speedometer and/or Odometer Inaccurate or Inoperative Gas

Step

Action

Value(s)

Yes

No

Schematic Reference: Instrument Cluster Schematics

1

Did you perform the Instrument Cluster Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Instrument Cluster

2
  1. Install a scan tool.
  2. Raise the vehicle drive wheels. Refer to Lifting and Jacking the Vehicle in General Information.
  3. Start the engine.
  4. Place the transmission into drive for automatic transmission or third gear for manual transmission.
  5. With the scan tool, observe the VSS parameter in the PCM Engine Data 1 data list.

Does the VSS parameter match the speedometer display?

--

Go to Step 3

Go to Step 4

3

Does the odometer operate properly?

--

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 6

4

Test the vehicle speed signal circuit for an open or a high resistance between the IPC and the PCM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 7

Go to Step 5

5

Inspect for poor connections at the harness connector of the IPC. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 7

Go to Step 6

6

Replace the IPC. Refer to Instrument Cluster Replacement .

Did you complete the replacement?

--

Go to Step 7

--

7

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2

Speedometer and/or Odometer Inaccurate or Inoperative Diesel 6.6L

Step

Action

Value(s)

Yes

No

Schematic Reference: Instrument Cluster Schematics

1

Did you perform the Instrument Cluster Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Instrument Cluster

2
  1. Install a scan tool.
  2. Raise the vehicle drive wheels. Refer to Lifting and Jacking the Vehicle in General Information.
  3. Start the engine.
  4. Place the transmission into drive for automatic transmission or third gear for manual transmission.
  5. With the scan tool, observe the VSS parameter in the ECM Engine Data 1 data list.

Does the VSS parameter match the speedometer display?

--

Go to Step 3

Go to Step 4

3

Does the odometer operate properly?

--

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 9

4
  1. Turn OFF the ignition
  2. Disconnect the ECM connector C2.
  3. Turn ON the ignition, with the engine OFF.
  4. Measure the voltage from the vehicle speed signal circuit to a good ground

Does the voltage measure greater than the specified value?

9.5 V

Go to Step 6

Go to Step 5

5

Test the vehicle speed signal circuit for an open, a short to ground or a high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 7

6

Test the vehicle speed signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 8

7

Inspect for poor connections at the harness connector of the IPC. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 9

8

Inspect for poor connections at the harness connector of the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 10

9

Replace the IPC. Refer to Instrument Cluster Replacement .

Did you complete the replacement?

--

Go to Step 11

--

10

Important:: Program the replacement ECM.

Replace the ECM. Refer to Engine Control Module Replacement in Engine Controls - 6.6 L.

Did you complete the replacement?

--

Go to Step 11

--

11

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2