GM Service Manual Online
For 1990-2009 cars only

Speedometer Inoperative

Step

Action

Value(s)

Yes

No

1

Were you sent here from the IPC Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Instrument Cluster

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, attempt to establish communications with the PCM.

Does the scan tool communicate with the PCM?

--

Go to Step 3

Go to Powertrain On Board Diagnostic (OBD) System Check

3

Select PCM display DTC function on the scan tool.

Does the scan tool display DTC P0500 or P0608?

--

Go to Powertrain On Board Diagnostic (OBD) System Check

Go to Step 4

4

With a scan tool, select IPC special functions and command a sweep test (minimum to maximum) on the speedometer.

Does the scan tool control the speedometer?

--

Go to Step 5

Go to Step 9

5

  1. With a scan tool, observe the Vehicle Speed parameter in the IPC data list.
  2. Test drive the vehicle as needed.

Does the scan tool indicate the correct Vehicle Speed?

--

Go to Step 6

Go to Step 7

6

  1. With a scan tool, observe the Vehicle Speed parameter in the IPC data list and the speedometer display on the IPC.
  2. Test drive the vehicle as needed.

Does the scan tool display correspond with the speedometer display within the specified value?

4.8 km/h

(3 mph)

System OK

Go to Step 9

7

  1. With a scan tool, observe Vehicle Speed parameter in the PCM data list.
  2. Test drive the vehicle as needed.

Does the scan tool indicate the correct Vehicle Speed?

--

Go to Step 8

Go to Powertrain On Board Diagnostic (OBD) System Check

8

Test the vehicle speed sensor circuit for an open, short to voltage, or short to voltage. Refer to Circuit Testing and Wiring Repairs

Did you find and correct the condition?

--

Go to Step 10

Go to Step 9

9

Replace the IPC assembly. Refer to Instrument Cluster Replacement .

Did you complete the replacement?

--

Go to Step 10

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10

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2