87 blower motor

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Wallace6

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Ok so I have tagged on to a post below about heater blower motor. It's getting cold up north.
I honestly need to know what wire will trigger the blower motor, directly off the battery. I'm not trying to start throwing parts at it.
I bought the relay that the purple wire goes into and connects to nothing. I tried both and the relay does click.
I really just want to make sure the blower motor spins, straight off the battery before wasting more money.
Thanks
 

mtbadbob

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There is supposed to be a single wire from the relay to the blower motor. I'm thinking it is purple. There should be a big red wire that runs to the relay. Once the key is on, the relay throws 12v to the single terminal on the blower. I just had an issue with mine where I had the voltage to the blower, but it wasn't doing anything until I hit it with the side of my fist, then everything took off & ran like it should. For whatever reason, it wasn't making contact in the blower, or it was frozen up, but it's been fine ever since. Do you have a 12v stab tester to test the wires?
 

Wallace6

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Ok can anyone please tell me where the purple wire connects? Thank you
 

RustyPile

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Look at the blower motor. There is only one wire connected to it. Never mind the color, or what it's connected to on the other end.. None of that is important to this test.. Disconnect that wire from the blower.. Using a suitable jumper wire, connect one end of your jumper to the positive battery post. connect the other end to the blower.. The blower should start running.. If not, the blower motor is probably bad..

With all due respect, Wallace6, if you can't figure how this simple test, you should seriously consider engaging some hands on help from someone locally.
 

Bextreme04

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Ok can anyone please tell me where the purple wire connects? Thank you
The blower motor power comes from two different spots. when the fan switch is on Hi, it trips the relay and makes a direct connection from that large red wire that runs across the firewall above the engine and goes to the bulkhead circuit breaker block near the brake booster. If the blower motor switch is anywhere except Hi, it runs through the fan switch and the blower motor resistors before going into the blower motor. My system needed a new fan, fan switch, and a new relay before it functioned properly and reliably.
 

Wallace6

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I have power down the line. My purple wire out of the relay is just hanging there. I have an ac vehicle and it's not simple to see what's going on.
Thanks all
 

Bextreme04

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I have power down the line. My purple wire out of the relay is just hanging there. I have an ac vehicle and it's not simple to see what's going on.
Thanks all
Post a Pic? My AC equipped truck has a big red wire going into the relay providing direct power to the blower motor when Hi is selected. Then there are a few wires coming from the blower motor resistor going into the relay that are various shades of yellow and green. Then the purple wire goes straight to the blower motor. Is there no end on it? Do you not have anything connected to the blower motor?
 

PrairieDrifter

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If you want to work on old trucks, you have to put in the effort. The wires aren't going to magically pop out at you and we can't do it for you. Just tellin it how it is.
 

Wallace6

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If you want to work on old trucks, you have to put in the effort. The wires aren't going to magically pop out at you and we can't do it for you. Just tellin it how it is.
Oh I'm well aware been building truck for years,just certainly things I need to ask help for but I appreciate your comment
 

Wallace6

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This is my purple wire and it's definitely different with the large ac box
 

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Wallace6

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I can certainly move it, where the heck does it plug in?
 

RustyPile

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I can certainly move it, where the heck does it plug in?
Several people have already told you where it goes, but I'll chime in one more time before I have to leave here and sort out the wires on my stereo..

Wallace, it plugs onto the little spade connector on the blower motor.. Do you not recognize the blower motor???
 

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