GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2001 🢒 Tahoe - 2WD 🢒 Engine 🢒 Engine Controls - 4.8L, 5.3L, and 6.0L 🢒 DTC P0500

Object Number: 730963 Size: SF
Master Electrical Component List
OBD II Symbol Description Notice

Circuit Description

The vehicle speed sensor (VSS) assembly provides vehicle speed information to the powertrain control module (PCM). The VSS assembly is a permanent magnet generator. The VSS produces an AC voltage as the rotor teeth on the output shaft of the transmission (2WD) or transfer case (4WD) pass through the sensor's magnetic field. The AC voltage frequency and amplitude increase as the vehicle speed increases.

If the PCM detects no vehicle speed during a specified length of time while other sensors indicate that the vehicle is moving, DTC P0500 sets. DTC P0500 is a type B DTC.

Conditions for Running the DTC
    • No manifold absolute pressure (MAP) sensor DTCs P0106, P0107 or P0108.
    • No throttle group DTCs P0121, P0122, P0123, P1120, P1125, P1220, P1221, P1514, P1515, P1516, P1517, or P1518.
    • No crankshaft position sensor DTCs P0335 or P0336.
    • The ECT is greater than 35°C (95°F).
    • The TP sensor angle is 5-100 percent.
    • The engine speed is greater than 1000 RPM.
    • (Diesel) The turbo boost pressure is 40-100 kPa (6-15 psi).
    • (Gasoline) The MAP is 40-100 kPa (6-15 psi).
    • All of the above conditions are met for 2 seconds.

Conditions for Setting the DTC

(Gasoline Engines) The PCM detects no vehicle speed for 50 seconds.

(Diesel Engines) The PCM detects no vehicle speed for four seconds.

Action Taken When the DTC Sets
    • The PCM illuminates the malfunction indicator lamp (MIL) on the second consecutive drive trip that the diagnostic runs and fails.
    • The PCM disables cruise control.
    • The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM records this information as Freeze Frame and Failure Records.
    • The PCM stores DTC P0500 in PCM history.

Conditions for Clearing the MIL/DTC
    • The PCM turns OFF the MIL after three consecutive ignition cycles in which the diagnostic test runs and passes.
    • The PCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the PCM.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are present by this diagnostic or any other emission-related diagnostic.
    • A scan tool can clear the MIL/DTC.

Step

Action

Value(s)

Yes

No

1

Did you perform A Diagnostic System Check - Engine Controls?

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Go to Step 2

Go to Diagnostic System Check - Engine Controls (6.6 L) or Diagnostic System Check - Engine Controls (8.1 L)

2
  1. Install a Scan Tool .
  2. Turn ON the ignition, with the engine OFF.

    3. Important: Before clearing the DTC, use the scan tool in order to record the Freeze Frame and Failure Records from the PCM.

  3. Record the DTC Freeze Frame and Failure Records.
  4. Clear the DTC.
  5. Turn OFF the ignition.

    6. Caution: To avoid any vehicle damage, serious personal injury or death when major components are removed from the vehicle and the vehicle is supported by a hoist, support the vehicle with jack stands at the opposite end from which the components are being removed and strap the vehicle to the hoist.

  6. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  7. Start and idle the engine.
  8. Turn off the traction control system, if equipped.
  9. Shift the transmission into third gear.
  10. Slowly release the clutch pedal.
  11. Slowly increase the engine speed to 1500 RPM.

Does the Scan Tool indicate a vehicle speed above the specified value?

24 km/h (15 mph)

Go to Intermittent Conditions (6.6 L) or Intermittent Conditions (8.1 L)

Go to Step 3

3
  1. Turn OFF the ignition.
  2. Disconnect the VSS electrical connector.
  3. Install the appropriate connector test adapters from the J 35616 connector test adapter kit on the sensor.
  4. Connect the black lead of the J 39200 digital multimeter (DMM) to pin A of the VSS.
  5. Connect the red lead of the J 39200 DMM to pin B of the VSS.
  6. Select AC Volts of the J 39200 DMM.
  7. Start and idle the engine.
  8. Turn off the traction control system, if equipped.
  9. Shift the transmission into third gear.
  10. Slowly release the clutch pedal.
  11. Slowly increase the engine speed to 1500 RPM.

Does the DMM indicate a voltage above the specified value?

1.2 volts

Go to Step 4

Go to Step 9

4
  1. Turn OFF the ignition.
  2. Connect a 12 volt test lamp to B+.
  3. Probe the VSS low circuit (CKT 822).

Is the test lamp illuminated?

--

Go to Step 5

Go to Step 10

5
  1. Leave the ignition OFF.
  2. Disconnect the PCM connector C2. Refer to Powertrain Control Module (PCM) Replacement (6.6 L) or Powertrain Control Module Replacement (8.1 L) in Engine Controls.
  3. Turn ON the ignition.
  4. Use the J 39200 DMM in order to test for voltage on the VSS high circuit (CKT 821) at Pin 21 of connector C2.

Is the voltage above the specified value?

0.2 volts

Go to Step 7

Go to Step 6

6
  1. Test the VSS high circuit (CKT 821) for the following conditions:
    2. • An open circuit. Refer to Testing for Continuity in Wiring Systems.
    • A short to ground. Refer to Testing for Short to Ground in Wiring Systems.
  2. Perform the necessary wiring repairs. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct a condition?

--

Go to Step 8

Go to Step 11

7

Repair the short to voltage on the VSS high circuit (CKT 821). Refer to Wiring Repairs in Wiring Systems.

Is the action complete?

--

Go to Step 12

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8

Repair the open or high resistance in the VSS high circuit (CKT 821). Refer to Wiring Repairs in Wiring Systems.

Is the action complete?

--

Go to Step 12

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9

Important: Inspect the reluctor wheel on the transmission output shaft (2WD) or transfer case output shaft (4WD) for excessive runout, slippage, missing teeth, or damage.

Replace the VSS. Refer to the appropriate procedure from the following list:

    •  Vehicle Speed Sensor
    •  Transfer Case Speed Sensor Replacement in Transfer Case NVG 149-NP
    •  Transfer Case Speed Sensor Replacement in Transfer Case NVG 236/246-NP8
    •  Transfer Case Speed Sensor Replacement in Transfer Case NVG 261-NP2
    •  Transfer Case Speed Sensor Replacement in Transfer Case NVG 263-NP1

Is the action complete?

--

Go to Step 12

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10

Repair the open in the VSS low circuit (CKT 822). Refer to Wiring Repairs in Wiring Systems.

Is the action complete?

--

Go to Step 12

--

11

Replace the PCM. Refer to Powertrain Control Module (PCM) Replacement (6.6 L) or Powertrain Control Module Replacement (8.1 L) in Engine Controls.

Is the action complete?

--

Go to Step 12

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12
  1. Select DTC
  2. Select Clear Info.
  3. Operate the vehicle within the Conditions for Running the DTC, as specified in the supporting text.
  4. Select Specific DTC.
  5. Enter DTC P0500.

Has the test run and passed?

--

System OK

Go to Step 1