DTC P0500 & P0501: VSS Range/Performance Problem

NOTE: DTC P0500 indicates a malfunction or low voltage problem in VSS circuit. DTC P0501 indicates a range/performance problem malfunction in VSS circuit. DTC P0500 and DTC P0501 are not used the same on all models. For example, on Accord 2.2L, DTC P0500 is used for VSS malfunction on M/T equipped vehicles and on Accord 2.7L, DTC P0500 is used for VSS low voltage problem on A/T equipped vehicles. Testing is similar for all models.

Test drive vehicle. Using scan tool, check vehicle speed. If correct speed is not indicated, go to next step. If correct speed is indicated, problem is intermittent, system is okay at this time. Check for poor connections or loose wires between VSS and PCM. See the WIRING DIAGRAMS article. Repair as necessary.
CAUTION: On vehicle equipped with Active Torque Transfer System (ATTS), DO NOT use engine to rotate one wheel when opposite wheel is on the ground. Vehicle could suddenly lurch forward.
Turn ignition off. Block rear wheels and set parking brake. Raise and support front of vehicle. Turn ignition on. Block right front wheel and slowly rotate left front wheel by hand. Measure voltage between PCM connectors terminal A9 and terminal C18. See Figure . If voltage does not pulse zero and 5 volts, go to next step. If voltage pulses zero and 5 volts, substitute a known-good PCM and recheck. If symptom or indication goes away, replace original PCM.
Turn ignition off. Disconnect PCM 31-pin connector "C". Turn ignition on. Block right front wheel and slowly rotate left front wheel by hand. Measure voltage between PCM connector terminal A9 and terminal C18. If voltage pulses zero and 5 volts, substitute a known-good PCM and recheck. If symptom or indication goes away, replace original PCM. If voltage does not pulse zero and 5 volts, repair a short or open in wire between PCM and VSS. See the WIRING DIAGRAMS article. If wire is okay, check VSS. See the SYSTEM/COMPONENT TESTS article.