Allante V8-273 4.5L (1991)
Vehicle Speed Sensor: Component Tests and General Diagnostics
Test A PCM Output Test (Table 1)
Test A - Table 1
Refer to table.
If voltages are correct, the PCM vehicle speed output to the IPC is OK. Replace the Instrument Panel Cluster (IPC) if the speedometer does not operate.
Test A PCM Output Test - Table 2