Fan not turning on

[earnies2]

(06-11-2018 )Nilao Wrote:  The prostar will throw a code of you wire the fan to a switch. It monitors the current in the ground side and when you cut the ground wire to splice in the switch the ecm loses the reference voltage and throws the check engine light everytime yo break the circuit.

The only way to do this is to wire in the switch and suppress the code in the ecm program.

so of I am understanding this when the ground is broken the fan turns on or does the BCM/ECM supply the ground to complete the circuit and wiring a switch in would set a CEL.