1993 Ford F-150 No Start When Hot

Suggested Repair

With the key in Start, check for voltage at the starter solenoid S terminal. If there is no power, trace the circuit back through the neutral safety switch and ignition switch, and confirm the starter relay is properly grounded. Add a starter heat shield if one is not already installed.

Conversation Summary

A 1993 Ford F-150 5.0 owner says the starter engages when cold but not when hot, even after replacing the fender-mounted starter relay and repeatedly splicing the solenoid lead. The expert advises checking voltage at the solenoid S terminal during crank, tracing a no-power condition through the neutral safety switch and ignition switch, and verifying the relay ground. A starter heat shield was also suggested.