why does my blower motor only work with a jumper wire and not a relay?

Question

I own a 99 cavalier 2.2 with a/c. My fan only blows on the 2 highest settings. It doesn't shut off with my car I have to shut it off. When I tried replacing the jumper with a relay I got for the blower motor it wouldn't turn on at all. The relay next to it seems to have been exposed to heat possibly from the previous relay melting. Is the resistor at fault? Did I just get à dud relay? I'd really like to fix this issue as soon as possible.

Answer 1

Being GM tech I have run into this problem many times it is almost always a bad resistor. It can also be caused by a burned connector to the resistor If you find a burned connector replace it and the resistor.

Answer 2

Three things that were the causes for the problems: The blower's resistor, the switch and the blower relay. My explanations:



The cause could be just a defected relay, why don't you replace it in the first place if the blower DID NOT shut off with no key in the ignition (Sticking relay).



The next cause that I would check will be the switch to turn the blower on or off. You did not say anything about if you've ever turned the switch to other positions to see how it work: LOW-MEDIUM-HIGH speeds.



Next one is a defected resistor that works only on the Medium and High speeds and not the Low speed. A total failed resistor will put the blower motor in default mode: High speed.



Look at the wiring diagrams I've included below. You'll have to scroll to the right one, I'm looking at number 9 diagram for a J body 1995. Works the same just differ in wires color.



http://www.autozone.com/autozone/repairinfo/repairguide/repairGuideContent.jsp?pageId=0900c1528003cfdd



Look at the diagrams or let someone help you how the circuit run, it'll be more than one failed components like I've explained above or it could be in the wiring. That where the wiring diagrams for: Helping you to see where you're going just like a road map.



Hope it help you, the circuit is simple. Feels good when you repair your own car. Happy wrenching.HTH



Edit: Don't hesitate to send a message if you need more help.

Answer 3

I'm confused trying to understand your jibberish.



You have had melted relays and you have things running on when the ignition is turned off?



I would strongly advise for you to go to an auto electrician, or have a good look at the wiring under the relay block which is probably melted and fused together.

Answer 4

sounds like you need another relay ! the relay is what turns the fan on and off ! try replacing that and if that don,t work then it might be the switch on the dash !

Answer 5

I think no one here can know the answers before they see the machine and the problem. Sorry:)