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blower motor not working

PostPosted: Sun Jan 31, 2016 4:23 am
by mirage_brat
well im back again with another question that has me stumped... i recently did a heater core in my car and the blower motor worked fine but my dash lights went all goofy when i put the dash back in due to a missing ground wire that i forgot to hook up... so i hooked it up and now the blower motor does work :?: :bang: :evil: the fuse is good... any suggestions????

Re: blower motor not working

PostPosted: Sun Jan 31, 2016 9:10 am
by cjbiagi
Do you have voltage at the terminal for the motor? If not, go back to the switch on the dash and see if you have input voltage there. Once you get it narrowed down you should be able to isolate the problem. Knowing if the issue is either before the switch or after should help us figure it out.

Re: blower motor not working

PostPosted: Sun Jan 31, 2016 9:30 am
by spencerforhire
The blower motor grounds through the heater housing. If it's not bolted in tight, or if you have a lot of paint or sealant around the mounting flange, it might not work. You can install a ground wire from one of the blower mounting screws directly to the body to check.

Re: blower motor not working

PostPosted: Sun Jan 31, 2016 7:19 pm
by Smiley
If it is an AC car it may need a ground wire to the blower motor itself, AC plenum is fiberglass.

Re: blower motor not working

PostPosted: Mon Feb 01, 2016 6:30 pm
by spencerforhire
Good point on the A/C heater box; I've only ever had one h-body with air, so I tend to forget about the non-conductive fiberglass ones.

Re: blower motor not working

PostPosted: Tue Feb 02, 2016 4:54 pm
by mirage_brat
i bought a new relay for it but havent had time to install it

Re: blower motor not working

PostPosted: Wed Feb 03, 2016 9:29 pm
by spencerforhire
Don't take this the wrong way; here comes a lecture from someone who makes his living working on automotive electrical systems-
1- When asking for advice, please provide all vehicle info; year, make, model, and any options(like A/C) that are pertinent to the problem.
2- Also please tell us what you've recently changed, and what you've checked so far(you did do this, thank you).
3- There is no substitute for a little investigation work with a meter or test light. It doesn't have to be fancy; an old tail light socket and bulb will work in a pinch.
4- Don't just throw parts at it and hope to stumble upon the problem. Expensive AND frustrating.
5- When you do find the problem, please let the Forum members know what it was and your solution.

I try to help out on here whenever I can with electrical problems, but only check in early morning and late evening; response time will vary. :wink:

Re: blower motor not working

PostPosted: Tue Feb 16, 2016 6:36 am
by mirage_brat
well i changed the blower motor relay and checked the resistors and fuse (checked out fine)... plus i hooked up another gorund under the dash.

Re: blower motor not working

PostPosted: Wed Feb 17, 2016 5:11 am
by zeke
There is a 3 pin connector, under the dash, that provides power to the blower switch harness, check and see if you plugged that back in.

Re: blower motor not working

PostPosted: Wed Feb 17, 2016 5:38 am
by zeke
Make sure this is plugged all the way in and the spade terminals are seated all the way in their connector housings.

blowerfeed.jpg



Simplified blower schematic:

hbody_blower_schematic.jpg

Re: blower motor not working

PostPosted: Mon Mar 21, 2016 9:43 am
by 78 starfire
I am having problems with the blower motor on my 78 starfire sx.... I am getting a clicking in the relay but the motor does not turn. I am not sure if it has to due with the green/black wire running as the ground not connecting to the ground on the car itself. (this being the prong it is connected to the green/black plug is grounded at the moter itself). If that is the case it may be fine, but I have tested the motors I have and they both work. This is frusterating. :bang:

Re: blower motor not working

PostPosted: Mon Mar 21, 2016 11:34 am
by zeke
Check for ground and power coming from the motor wires with a test light. Relay could have bad contacts. You can pull relay connector off and jump out the battery terminal to motor terminal and see if it runs then.

Do your lower speeds work fine?

Re: blower motor not working

PostPosted: Thu Mar 24, 2016 7:09 am
by mirage_brat
im not getting power anywhere for the blower motor or switch :bang: :bang:

Re: blower motor not working

PostPosted: Thu Mar 24, 2016 9:25 am
by zeke
Did you check the 3 pin connector? Is there power there?

Re: blower motor not working

PostPosted: Fri Mar 25, 2016 1:02 pm
by 78 starfire
Is there any wiring diagram you guys would have I could look at I have a subcompact Manuel but it has no diagrams :bang: nor does it help me with the other problem I have on her