need some advice on this one , best to ask

[GOPAPA]

so ,,,,,,I been replacing all the switches and resisters and relays under the dash ,,just so hopefully I will not need to do it again ,,as it takes two pair of glasses at different distances to see what I am doing,, know what I mean ? lol

I replaced my heater/Ac blower switch out for one of the switches .. I have replaced the replay ///the resister /// and the dieseling switch

I put in the new blower switch and now before I hook it all up to hot wire ,,I want to check the blower motor for amperage draw.. BUT I do not want to use my new blower switch to check out the amps for fear of ruining the switch ,,

This is my delema ,, any one done this before and can guide me how to do it with out maybe ruining my new switch thru the different amp draws of the blower motor ?

[truckster]

I'm not sure about the answer to your question, but I had to laugh about the glasses. I sometimes find myself doubling up my reading glasses for close-up detail work.

[truckster]

You could hotwire to the blower motor from the battery to check for amperage draw.

You need a multimeter capable of checking amperage, obviously. Hook up the multimeter in line from the battery to the terminal on the blower motor. You should get an amperage reading that way. I think it's a 20 amp circuit, so that's the range you'd be looking at.

Sorry, I was watching a football game when I answered earlier.

[LongBox]

Any old automotive ammeter should do this job. Good idea to check. Just get 12 V from an unfused point anywhere under the dash, go through the ammeter, and hook up to the motor. The gauge should read the amps the motor draws.

[GOPAPA]

What I was wondering is ,,how do I check the amps drawn by the low speed of the fan compared to the fast speed with out a switch ? I know that if the blower motor uses more that 17 amps then it could ruin my switch .. I am assuming that I am getting the low speed when hot wire ing it straight to the battery ???

[truckster]

When you hotwire to the battery you're getting high speed. The resistors reduce the speed. The only way you can check the current draw at low speed is to run it through the largest resistor.

[GOPAPA]

Originally Posted by truckster

When you hotwire to the battery you're getting high speed. The resistors reduce the speed. The only way you can check the current draw at low speed is to run it through the largest resistor.

Thanks truckster ,,I was thinking that ,, about the resisters, It is the high speed draw that can sometimes ruin a switch if there is a bad blower motor..