System Operation: Speedometer

The PCM calculates the vehicle speed from the transaxle OSS sensor input and from the tire size and axle ratio configuration in the PCM VID block. The PCM provides the IPC with a vehicle speed data message to command the speedometer pointer.

The IPC provides a tolerance which allows the gauge to display between 3% lower and 7% higher than the actual vehicle speed. This means that with an actual vehicle speed of 96.6 kmh (60 mph), the speedometer may indicate between 93.7 kmh (58.2 mph) and 103.3 kmh (64.2 mph), which is normal.