Is it ok to short out a control wire from the PCM?

I’m thinking about putting in a switch to ground from the green/white relay control wire for the Radiator Fan Control Relay as I can’t get the PCM to turn the fan on, even though everything else tests OK, and the fan runs fine once the relay closes.

(1993 Chevy Corsica).

If I don’t disconnect the control wire from the PCM (power control module), could this damage a component in the PCM?

I posted you an answer to this question in another thread.