new resistor but no blower...why?!

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Honky Kong jr

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Ill hafta buy one
Logic probes are helpful too. They've come down in price. That's my tool of choice in these situations. They have a green LED for ground signals and a red LED for 12v the will have 2 clamps that hook to the battery.
 

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Logic probes are helpful too. They've come down in price. That's my tool of choice in these situations. They have a green LED for ground signals and a red LED for 12v the will have 2 clamps that hook to the battery.
Oh damn thats handy
 

Camar068

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Honky Kong jr

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That sucker have a voltage display too, or just the red/green LEDs?
Just green and red. I have a power probe too, it lets you feed 12v and has a circuit breaker built in, but they can be dangerous lol you can pop an ECM pretty quick if you give 12v to the wrong thing.
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This is the one I use it's a MAC I believe it's the only MAC tool I own lol
 

bucket

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I've got a snap on light with a digital voltage display in it and it also backlights red or green. But it just has the one clamp, so of course you gotta keep switching the clamp around to test power and ground. It would be great if it had a power and ground clamp on the lead.
 

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I've got a snap on light with a digital voltage display in it and it also backlights red or green. But it just has the one clamp, so of course you gotta keep switching the clamp around to test power and ground. It would be great if it had a power and ground clamp on the lead.
No meter but has a positive and negative clamp. It's good for checking injector pulses, among other things.
 

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I really thought this thread was goin somewhere...ohhhh I dunno.....like TO THE SOLUTION maybe? :p

I was screwin with mine earlier today and I came here looking for which switch terminals to short that force the blower on high..
Will keep looking. This ain't the right thread but I DID just learn about that little relay thang...that's not what i'm thinking of. I thought it was in the switch?
I swapped resistors and switches in my squares today and now the K5's blower speed is much, much faster! :D But no "high".
 
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75gmck25

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The first three blower speeds are controlled by the resistors, but on A/C vehicles the high speed is a separate line.

High speed fan uses the blower relay, which is the silver box you see in post #9, with the "always on" power connection. The "always on" power for this relay is through an inline fuse that is located on the top of the firewall, and the wire runs over to the the power junction near the PB booster. When blower motors go haywire they seem to draw too much power for this 30 amp inline fuse, which burns up the fuse holder and blows the fuse. I replaced mine with a new blade fuse holder and 30 amp fuse, and haven't had trouble since.

One reason they use the relay for high speed is that when you put the A/C on max it puts the vacuum doors into recirculate mode, and also puts the blower motor on high. That relay is used to put the blower motor on high.

Bruce
 

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Dangggg.
I always wondered what that fuse holder was supposed to do! There's the trouble for sure!
Thanks a ton Bruce, you're a good ol boy! :gay:

I was about to buy the little silver relay thingy on the side of the heater box and it STILL wouldn't have worked!.

I never did find the thread I was lookin for....thank you again.
 

78C10BigTen

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The first three blower speeds are controlled by the resistors, but on A/C vehicles the high speed is a separate line.

High speed fan uses the blower relay, which is the silver box you see in post #9, with the "always on" power connection. The "always on" power for this relay is through an inline fuse that is located on the top of the firewall, and the wire runs over to the the power junction near the PB booster. When blower motors go haywire they seem to draw too much power for this 30 amp inline fuse, which burns up the fuse holder and blows the fuse. I replaced mine with a new blade fuse holder and 30 amp fuse, and haven't had trouble since.

One reason they use the relay for high speed is that when you put the A/C on max it puts the vacuum doors into recirculate mode, and also puts the blower motor on high. That relay is used to put the blower motor on high.

Bruce
Would this be it??

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