S1: Check Tachometer Signal
With the ignition key in the OFF position, remove the instrument cluster. Leave the instrument cluster connected. Connect the Rotunda 88 Digital Multimeter 105-00053 or equivalent to measure engine speed. Turn the ignition key to the ON position allowing for the engine to be running. Measure the voltage on terminal 4 of the instrument cluster connector C3 on the back of the instrument cluster at the following engine speeds, see SPEED TO VOLTAGE COMPARISON .
SPEED TO VOLTAGE COMPARISON
| Engine Speed | Voltage |
|---|---|
| 1000 RPM | 1.69 Volts |
| 1500 RPM | 2.64 Volts |
| 2000 RPM | 3.44 Volts |
| 2500 RPM | 4.50 Volts |
| 3000 RPM | 5.22 Volts |
Are the voltages OK? If yes, replace the instrument cluster. If no, check for problem in wiring to PCM. Check for possible faulty vehicle speed sensor signal to PCM. See 1995 ENGINE PERFORMANCE FORD MOTOR CO. - SELF-DIAGNOSTICS, VILLAGER .