Speedometer Inoperative/Inaccurate: Description

Vehicle Speed Sensor (VSS) uses a permanent magnet alternator to produce an electrical signal of 24,000 pulses per mile to represent vehicle speed. This signal is sent to Powertrain Control Module (PCM), which sends a 4000 pulse-per-mile signal to IPC through circuit No. 817 (Dark Green wire). IPC supplies voltage to circuit No. 817, and PCM pulses circuit to ground to transmit vehicle speed.