O.K.-I flunked "Electrical Networks" and need help. I want to replace the clutch driven mechanical fan with a high-flow electrical fan. I want to wire something up such that if the electrical fan fails and hence, the circuit is broken, then my wiring/electrical components get 12Volts and then I get a buzzer or light lit off on the dashboard. This way, I don't get excessive engine temp and warp my head(the one on the car).

TIA

-Matt

/// The key would be to install a relay coil across the fuse, or a twelve volt bulb across the fuse. (There is a fuse in the motor/relay/battery circuit) When the fuse fails the path through that circuit is through the bulb. The motor winding should not be enough to dim the bulb.

A small relay in parallel with the power to the fan motor will indicate power loss (fuse does not blow) if wired normally closed when the relay is off. It would be on until the thermostat turns the fan on. With two lights and a single pole double throw relay you could indicate power off/on.

This could get complicated depending on what information you want remotely indicated.

Simple solution, you can hear the motor in the FM radio unless you have shielding and filtering in the power wires.

I'm not sure how to wire the warning setup , but if you are going to go completly electric I might recomend what I've done on another vehicle/ electric fan conversion which is along with the big fan , mount a small auxillary fan wired to seperate relays with auto reset circuit breakers instead of fuses , as a backup.

I have this setup on my chevy van and that little backup fan saved us from disaster on a vacation a couple of years ago.

--------Robert