Electrical issues

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VAL

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When my truck is on, everything works fine. But my headlights get brighter, and blower motor makes a funny sound when I rev it up. is that normal?
 

89Suburban

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How is your voltmeter reading?
 

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Alternator putting out to many volts? Maybe a bad ground? See what your alternator is putting out at idle and higher rpms
 

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The voltmeter reads 13 at idle, 15 at rev or while driving.
 

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Usually a blower motor makes noise at lower speeds when its starting to go bad and clears up when it gets more voltage. May see how many volts the fan is getting when on high and engine running and revved up. 15v seems a bit high not much though.
 

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That does`nt seem too far out of line, is that with everything turned on ???
What sort of noise from the blower are we talking about, like is the motor squeeling or making sounds like a bearing going bad or is it just the sound of a lot more air moving.
With the headlamps on and blower running on high, the alternator, at engine idle speed, can not put out enough voltage to keep up with the amount of amps that everything is needing to run full efficient.
With a few RPMs involved, the alternator will come up to max output, as high as the voltage regulator will allow, and then there are enough amps to allow the electrical components to run at full effiency. as in, the headlamps and heater both running at the same time.
 

VAL

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The blower motor when on high, will actually go faster when I rev the engine up. That when it starts making a noise kinda like its in extra high(buzzing sound). I turned the engine off, and my windows are taking a whole 60 sec. to go up or down. I start the engine and windows start to work normal speed. I got a gremlin somewhere.
 

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Alternator provides higher voltage than just the battery alone. Perfectly normal for things to be dimmer/slower the engine is off, then pick up when the engine is running. Normal alternator output is usually between 13.8 to 14.6 volts. A typical fully charged battery is only 12.6 volts.
 

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If anything it could be a weakening battery with the colder weather around now that would show the alternator doing some more work. Mine pretty much does the same thing as yours. My cold cranking volts are low. Key on shows 9 or 10 volts on mine before I crank it on a cold morning but the amps are there to spin the starter. So I know I will be needing a battery in the near future. As far as the blower noise Kaye a leaf got in there and is hitting the fan blade. Just pop it out and check for or vacuum many debris out of there and put it back together and make sure the ground is good and clean. Then spray some of that battery terminal protector over the ground to seal and protect it.


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VAL

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Well, earlier I got stuck in the rain, and now my wipers are weakened. They were working just fine an it felt as they were struggling to move, and just stopped in the middle of one of the cycles. I turned the engine off, started it back up, wipers started working again.:wtf:
 

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You might have a fusible link starting to take a **** on you.
 

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Appears you are getting plenty of voltage out of the alternator.

The battery seems to be receiving and holding a charge - system never goes dead/truck always starts.

But the following would indicate it is getting weak (maybe add DI water to the cells?):

I turned the engine off, and my windows are taking a whole 60 sec. to go up or down. I start the engine and windows start to work normal speed.

Since system voltage looks good, the way the wipers, heater blower and H/L's are behaving makes it sound like you have a system grounding issue. The noise from the blower is probably just due to old age - worn motor bearings maybe.

Check the main ground connections.

Pull the cable connector clamp off the battery negative - clean the post and inside of the clamp.

Follow the cable to where it bolts to the engine (usually the alternator bracket). Remove the bolt. Clean the terminal faces (both sides) to bright metal with emery cloth or a Scotchbrite pad. Clean the underside of the bolt head the same way. Use a wirebrush and clean the threads of the bolt to bright metal.

Also check the cab to engine ground strap:

You must be registered for see images attach


Clean and tighten the connections and bolts on both ends.
 

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Any luck here VAL?

Really take a good look at that ground cable at the motor, I just saw mine is all ****** green corroded.

And you battery connections, make sure it don't have that white crap on them and are nice and snug.
 

VAL

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I did the big 3 upgrade not to long ago, cleaned up all the grounding points etc. I'm beginning to think there's something going on with the fuse block. My windows also might need switch replacement, along with my window motors. I'll keep looking.
 

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