DTC P0500: VSS Circuit Malfunction

NOTE: Before you troubleshoot, record all freeze data and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).

Reset the ECM (see HOW TO RESET THE ECM ).
Start the engine. Hold the engine speed at 3,000 RPM without load (in neutral) until the radiator fan comes on, then let it idle.
Test-drive with the transmission in 2nd gear. Accelerate to 4,000 RPM, then decelerate to 1,500 RPM with the throttle fully closed for at least 5 seconds.
Check for a DTC with a scan tool or the HDS.
Is DTC P0500 indicated?
1. YES - Go to step 5.
2. NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals between the VSS and at the ECM.
Turn the ignition switch OFF.
Raise the vehicle.
Disconnect the VSS 3P connector.
Turn the ignition switch ON (II).
Measure voltage between VSS 3P connector terminal No. 1 and body ground.

Fig 1: Measuring Voltage Between VSS 3P Connector Terminal No. 1 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 5 V?
1. YES - Go to step 11.
2. NO - Go to step 10.
Measure voltage between ECM connector terminal C28 and body ground.

Fig 2: Measuring Voltage Between ECM Connector Terminal C28 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 5 V?
1. YES - Repair open in the wire between the ECM (C28) and the VSS.
2. NO - Substitute a known-good ECM (see HOW TO SUBSTITUTE THE ECM FOR TESTING PURPOSES ) and recheck. If the symptom/indication goes away, replace the original ECM (see ECM REPLACEMENT ).
Measure voltage between VSS 3P connector terminals No. 1 and No. 3.

Fig 3: Measuring Voltage Between VSS 3P Connector Terminals No. 1 And No. 3
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 5 V?
1. YES - Go to step 12.
2. NO - Repair open in the wire between the ECM (B22) and the VSS.
Turn the ignition switch OFF.
Reconnect the VSS 3P connector.
Turn the ignition switch ON (II).
Raise the rear of the vehicle, and make sure it is securely supported. Hold one wheel, and slowly rotate the other.
Measure voltage between ECM connector terminals A9 and B22.

Fig 4: Measuring Voltage Between ECM Connector Terminals A9 And B22
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Does voltage pulse between 0 V and about 5 V?
1. YES - Substitute a known-good ECM (see HOW TO SUBSTITUTE THE ECM FOR TESTING PURPOSES ) and recheck. If the symptom/indication goes away, replace the original ECM (see ECM REPLACEMENT ).
2. NO - Go to step 17.
Turn the ignition switch OFF.
Disconnect ECM connector A (32P).
Turn the ignition switch ON (II).
Hold one wheel, and slowly rotate the other.
Measure voltage between ECM connector terminals A9 and B22.

Fig 5: Measuring Voltage Between ECM Connector Terminals A9 And B22
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Does voltage pulse between 0 V and about 5 V?
1. YES - Substitute a known-good ECM (see HOW TO SUBSTITUTE THE ECM FOR TESTING PURPOSES ) and recheck. If the symptom/indication goes away, replace the original ECM (see ECM REPLACEMENT ).
2. NO - Repair short or open in the wire between the VSS and the ECM, if the wire is OK, replace the VSS (see GAUGE ASSEMBLY REPLACEMENT ).