The blower fan in my a/c unit never stops even when the thermostat is off.
Everything else is working.
Could the relay be bad. How you wire a fan relay.
Thanks for your help

It may be a green wire from the thermostat, should turn off if disconnected at thermostat(bad thermostat), if still on may be a control wiring problem from thermostat to air handler or stuck relay/contactor.
Follow wiring back from blower to find capacitor and relay.
Capacitor is good.
Turn off power when working on unit.