DTC P0500 Vehicle Speed Sensor (VSS) Circuit

Circuit Description

A toothed wheel mounted on the output shaft of the transmission generates an AC voltage pulse as it moves past the Vehicle Speed Sensor (VSS). The VSS contains a permanent magnet surrounded by a coil of wire, which produces a magnetic field. The toothed wheel interrupts the magnetic field this generates an AC voltage pulse. As the vehicle speed increases the AC voltage pulse rate also increases.

Conditions for Running the DTC

• DTCs P0107, P0108, P0117, P0118, P0121, P0122, P0123, P0125, P0506, P0507 are not set.
• The engine coolant temperature is greater than 35°C (95°F).
• The engine speed is greater than 1000 RPM.
• The TP sensor angle is between 5.0% and 100%.
• The MAP is between 40 kPa and 100 kPa when the A/C is OFF.
• The MAP is between 45 kPa and 100 kPa when the A/C is ON.
• All conditions met for 2 seconds.

Conditions for Setting the DTC

The PCM detects vehicle speed at 0 km/h (0 mph) for 100 seconds.

Action Taken When the DTC Sets

• The PCM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
• The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC

• The PCM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
• A last test failed, or current DTC, clears when the diagnostic runs and does not fail.
• A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
• Use a scan tool in order to clear the MIL and the DTC.

Diagnostic Aids

Inspect all of the circuits to the PCM and the VSS. Inspect the terminal connections at the VSS harness connector and at the PCM harness connector. If all of the circuits and connections are OK, replace the PCM.

For an intermittent, refer to Symptoms .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

2. The ASR/TCS must be disabled when performing this step. Whenever the ignition key is cycled to the OFF position and then cycled back ON, the ASR/TCS system will default ON.

Step	Action	Value(s)	Yes	No
1	Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?	--	Go to Step 2	Go to A Powertrain On Board Diagnostic (OBD) System Check
2	Turn OFF the ignition. Raise the vehicle. Refer to Lifting and Jacking the Vehicle . Idle the engine. Disable the ASR/TCS systems, if so equipped. Place the transmission in 2nd gear and release the clutch pedal. Slowly bring the engine speed to 1,500 RPM and hold. Does the scan tool indicate a vehicle speed above the specified value?	15 mph (24 kph)	Go to Diagnostic Aids	Go to Step 3
3	Turn OFF the ignition. Disconnect the VSS electrical connector. Install the appropriate jumpers from the connector kit J 33431-B to the VSS (sensor side). Connect the black lead from the DMM J 39200 to pin A of the VSS and the red lead to pin B of the VSS. Set the DMM to the AC volt scale. Idle the engine. Place the transmission in 2nd gear and release the clutch pedal. Slowly bring the engine speed to 1,500 RPM and hold. Does the DMM indicate a voltage above the specified value?	1.20 V	Go to Step 4	Go to Step 9
4	Turn OFF the ignition. Probe the VSS low circuit (terminal A) using the test lamp J 39200 connected to B+. Is the test lamp illuminated?	--	Go to Step 5	Go to Step 10
5	Turn OFF the ignition. Disconnect the PCM connector C1 located on the opposite side of the manufactures logo. Refer to PCM Replacement/Programming . Turn ON the ignition. Measure the voltage from the VSS high circuit to a known good ground using the DMM J 39200 set to the DC volt scale. Is the voltage above the specified value?	0.2 V	Go to Step 7	Go to Step 6
6	Test the VSS high circuit for an open or short to ground. Refer to Testing for Continuity or Testing for Short to Ground in Wiring Systems. Did you find and correct the condition?	--	Go to Step 8	Go to Step 11
7	Repair the short to voltage on the VSS high circuit. Refer to Wiring Repairs in Wiring Systems. Is the action complete?	--	Go to Step 12	--
8	Repair the open/high resistance in the VSS high circuit. Refer to Wiring Repairs in Wiring Systems. Is the action complete?	--	Go to Step 12	--
9	Important Inspect the reluctor wheel on the transmission output shaft for damage. Replace the VSS. Refer to Vehicle Speed Sensor in Manual Transmission MM6. Is the action complete?	--	Go to Step 12	--
10	Repair the open in the VSS low circuit. Refer to Wiring Repairs in Wiring Systems. Is the action complete?	--	Go to Step 12	--
11	Important: Program the replacement PCM. Refer to PCM Replacement/Programming . Replace the PCM. Is the action complete?	--	Go to Step 12	--
12	Select the Diagnostic Trouble Code (DTC) option and the Clear DTC Information option using the scan tool. Idle the engine at the normal operating temperature. Select the Diagnostic Trouble Code (DTC) option and the Specific DTC option, then enter the DTC number using the scan tool. Operate the vehicle within the conditions for running this DTC as specified in the supporting text, if applicable. Does the scan tool indicate that this test ran and passed?	--	Go to Step 13	Go to Step 2
13	Select the Capture Info option and the Review Info option using the scan tool. Does the scan tool display any DTCs that you have not diagnosed?	--	Go to the applicable DTC table	System OK