Switch the ignition ON and check the voltage on VSS terminal
29 of the ECU.
The voltage should vary above and below 2 volts with the vehicle moving
slowly.
If the voltage varies above and below 2 volts, the VSS is functioning.
If there is no response, check for VSS signal at the rear of the instrument
panel. If no VSS signal is present, replace the VSS. If VSS signal is present
at the instrument panel, repair the harness.
Connect the VSS harness to the VSS. Backprobe the harness side of VSS connector
terminals with a high-impedance voltmeter.
Turn the VSS gear by hand. The voltmeter should show 0–5 volts switching
ON/OFF 4 times per revolution.
If there is no response, check the electrical connections, the ECU VSS signal
terminal connection, the voltmeter setting and the harness. If all these items
check out OK, replace the VSS.