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Bilbobowers
09-05-2023, 10:52 PM
Hey y’all working on my 89’ 2wd front and rear ac tv. Just changed out the front blower motor and resistor thinking that would solve my issue but to no avail.
so I am getting a click on my ac relay, no power to my ac fuse and and strange reading on the power right before my blower motor (42 volts?!)
this all started when my blower motor went out a couple months back, right before the Florida summer came in. I’m so lost for words, click on the ac relay, no click on the blower motor relay and no power on ac fuse.
maybe y’all can help me out before I put the dash back on it and take it to a mechanic!

williamfowers
09-09-2023, 06:05 PM
Anybody got any suggestions as to what this might be?

Burntboot
09-11-2023, 10:00 AM
A 42V reading from a 12V system would indicate either a problem with the meter or the way it is being used.

89van
09-11-2023, 11:52 PM
"so I am getting a click on my ac relay, no power to my ac fuse and and strange reading on the power right before my blower motor (42 volts?!)
this all started when my blower motor went out a couple months back, right before the Florida summer came in. I’m so lost for words, click on the ac relay, no click on the blower motor relay and no power on ac fuse."

No idea how you would get 42v out of a 12v system, unless youre running 4 batteries in-series to power an onboard sewage pump, automated bar and jacuzzi... but im guessing thats not the case. If you're using an analog meter like i do, try setting it to a setting high enough to read 12 (I.E. you have a 30-volt DC setting) or see if you reversed the polarity by mistake. assuming you don't have an analog meter, see if your auto-ranging is on.

Think how a circuit works. You need power, a ground, a load/loads, wiring, protection, and a switch/switches. Would be wise to check these within presumably your blower circuit. Don't have a wiring diagram, so it might be wise to find one! Digitally or physically... Luckily, automotive electricals are simply as in all we have are 12 volts DC and 0 volts. Before all the later-model vehicles is just this, anything newer might have a 5 volt reference voltage for modules and such.

Alright ill do my best to analyze this, with my limited knowledge so take it with a few grains of salt...

Click on your AC relay, no power to AC fuse, and no power to the blower relay

Knowing your AC relay is getting power, and assuming its 12v, you have power and ground there.

Is the fuse good? Assuming it is, moving on. If popping a same rating fuse into the ac fuse blows it immediately, means you have a short very close to the fusebox. Relays can internally short, would be wise to test your relay if it is good. Same for your blower relay, assuming they are good, trace your power flow. I guess from my limited experience SOME relays CAN click WITHOUT receiving 12v, so check how much it's getting; i.e. if it gets 9v and clicks, it might be deceiving! Then go find out why it's not getting 12v. Man, I'd kill for a wiring diagram to examine this problem right now!!! :anger: Anyone know of an online source maybe??

Also, don't get overwhelmed looking at a diagram, just isolate whats specific to the related circuit!

I am not an expert, this is just what I limitedly know within the scope of my knowledge. :lol: Hopefully, this might help.