Blown fuse

[dougw714]

i have a 90 pignose and after the clutch on my compressor seized up and the belt broke any time i turn the fan on it will burn the fuse (third down on the left). i have replaced the mode door motor because before all this it made some straining noise when changing from any position. I also had a extra temp control unit laying around and put that it but the same problem. The blower still works but when turned on the fuse blows and will not change the direction of the vent. if i replace the fuse i can change the direction of air flow but as soon as i turn the fan on the fuse will blow. any help would be greatly appreciated
Modified by dougw714 at 5:50 PM 10/19/2006

[rudy543us]

So the fuse blows as soon as you turn on the Ac blower motor, the fan motor that blow air thru you air vents? If this is true take the blower motor out and connect it directly to you batter and measure the amount of current you are drawing. in addition to this look at the motor is it turning fast or slow is it getting hot does the shaft feel real loose and you turn it with you hand very easy?

get back to me if you have any questions.

[dougw714]

Before removing the blower do you think i should test or replace the blower motor resistor. could that possibly be causeing this problem?

[rudy543us]

Sure Test it, but you have to remove it from the Circuit to do that. If you’re not the original owner and you have no records of previous maintenance it is a good possibility that is the original equipment. I’m not saying just start replacing parts but taking it out and clean the parts up. I know if it’s not broke don’t fix it, but at this point there is nothing to prove it is not broking, even if you feel air blowing.

I was reading what you route initially you said,

“after the clutch on my compressor seized up and the belt broke any time I turn the fan on it will burn the fuse”

So is there a separate switch to turn your AC on or does it turn both on when you flip the fan switch? If it turns the AC on as soon as you turn on the fan then most likely you have some kind of short were you were last working near the AC compressor. Now if you have separate switches for your AC and FAN then keep looking at the Fan and all related circuits.

[dougw714]

"So is there a separate switch to turn your AC on or does it turn both on when you flip the fan switch? If it turns the AC on as soon as you turn on the fan then most likely you have some kind of short were you were last working near the AC compressor."

i still have not replaced the the belt or the compressor. there is a seperate ac switch but it does not matter any position and the same fuse blows as soon as the fan is turned on. i read somewhere about a blower relay but have not been able to find it. with the fan off i have changed the direction sucessfully but noticed the intake door motor is very weak and makes straining noises (a little different then the mode door motor was making before being repaced). could this motor be causing the short and how hard a job is it to do?

[rudy543us]

With the fan unplugged does it still blow fuses?And you said still have not changed the compressor?

[dougw714]

I have not changed the compressor yet and with the fan unplugged the vent position changes but the same thing happens with the switch plugged in. the intake door motor makes some weird noises do you thinking its shorting out the system when the fan gets turned on or could the compressor be causing a short somewhere?

[rudy543us]

Here is what I’m trying to figure out; if you disconnect the Fan motor does the fuse still blow? Did this problem start when the compressor went out? Have you made any other changes that correspond with the time this problem started? I mean any thing a new radio a new part under the hood.

[dougw714]

No the fuse does not blow it only blowes when the fan is turned on.this did start when the clutch on the compressor blew.I have changed the motor that controls the vent direction(mode door motor) because it was making alot of noise when changing positions. i now hear noises coming from the other vent motor(intake motor) so i will try changing that. i think it could be related to the compressor somehow shorting out the system

[rudy543us]

So have you tried disconnecting the fan and with the fan disconnected turn the fan switch ON. This will tell you the fan is the problem. Please read what I am typing slowly and carefully you need to trouble shoot in steps not just jump from one place to another.

I’m not trying to be a d!ck but you can fix this problem real quick if you would just follow the steps

[180fan]

you've got a short in the fan wiring. time to go at it with a multimeter and find the short. This one shouldn't be so bad since it's only possible at a few wires.

[rudy543us]