Control Unit Connector

On Prelude models, check for voltage at control unit connector (Blue wire) with ignition on. There should be voltage. If there is no voltage, check Blue wire between ignition coil and control unit.
On all models, check for voltage at the Black/Yellow wire with ignition on. There should be voltage. If there is no voltage, check wiring. Check Brown/Black Wire Prelude) for continuity between control unit and ground. There should be continuity.