Winter mod - heater blower integrated with engine kill switch

[MetroMPG]

I keep thinking about this one....

(Not my heater.. just a random image)

My heater fan switch needs a dual "winter" and "summer" setting.

The problem is that in the winter, when the engine is stopped (via the kill switch) for more than a few seconds with the blower going, it very quickly cools off the heater core and starts blowing cold air on my poor toes/hands/windshield.

As a result, I find I'm frequently turning the fan off & on. Particularly when I'm doing a bit of P&G. Sometimes I forget to turn it back on until the cold starts seeping in again .

It would be nice to have a switch that would enable me to select whether I want the blower switch to operate, as designed with the key at "ON/RUN" position, or I could flip it and cause the blower to NOT run when the engine is stopped.

Thoughts?

[Coyote X]

The oil pressure idiot light is a pressure switch that turns on a light on the dashboard. Wire a standard automotive relay with the center pin on it to the light so when the light comes on it cuts power to the blower

A relay without that center pin would only let you have heat when the oil light is on.



87a is on until the relay is energized then 87 is on. so 30 and 85 go to the idiot light and 86 and 87a splice into the blower motor.

[MetroMPG]

Thanks - great idea.

And bonus: it can serve as a temperature warning if I lose my oil and don't notice the light!

Possibly a dumb question, but do you know if the pressure switch is on 12v? (Aren't some of the sensors lower voltage?)

[Coyote X]

It is probably going to be 12v. It was easier and cheaper for them just to use a 12v bulb and switch instead of having to use a voltage regulator and other junk in the circuit.

As a bonus you could add a switch on one of the relay wires going to the bulb to kill the relay so the blower motor runs like normal for summer use.