maximal01

Well as stated above my lights started to dim not a lot but just enough to be noticable, after searching for 2days i desided to just ask, well i had the battery tested it was better then new condition, the ac pump is completely shot, tried to refill it leaks everywhere, well is it possible that the ac pully is slowing the alternator down to much? i just cant think of anything else it could be i know that the compressor has a noise when the car is on i can hear it so would a bad bearing in the ac pully do this?

thanks jp

DennisMik

iTrader: (2)

Are your lights dimming when the engine rpm goes down to idle? or are they dim all the time? I don't think the ac compressor is causing this. I would measure the voltage with and without headlights on and see what that shows. The voltage should never go below 12 at any time except starting. 14.5 is about the max, but it won't be that at idle. At idle you should be around 13 volts. When you have the results, we can start looking at causes.

maximal01

i believe i had the battery tested it was reading 12.89 or .86 but it was fine, im taking it to get the alt checked

maximal01

ok thes results are 14.2 to start after everything is on its 14.14 so anyone?

Max_5gen

iTrader: (2)

If it does it at 1K rpm or less it's normal. What is the problem anyway? I don't understand "my lights started to dim" - could you give more details? Buy your own multimeter and measure battery voltage yourself. It should cost around $20, very useful tool. If unsure about results measure the voltage on another car, they're all the same.

maximal01

like a fast blink hardly noticed on the dash but the headlights alos when i put windows up 2 at a time, the rpms dropped buy about 300, an would go up when i would release the button

Max_5gen

iTrader: (2)

I just tried the same on my car and neither rpm nor headlights were affected. Do you mean rpm drop to around 400 as it normally idles slightly above 700?

No wonder alternator can't supply enough voltage to the system to keep the headlights up at 400 rpm. I assume 'alos' means your headlights become dim. Do you have other problems with idle like it goes down when you turn AC on or turn your steering wheel when car is at rest? No matter what alternator/battery are doing idle control system should not let idle to drop that much unless your battery is almost dead but then you'd experience starting problems as well which you never mentioned.

mandyfig

Clean your connections, looks like ground is not well "grounded." No pun intended. After I added grounding kits, I noticed a decline in the dimming or dropping of rpm's when operation the windows and headlamps.

taaron39

I think I'm having the same problem.... Lately my idle has been really low like 450 rpm... so when I turn my AC occassionally it will drop the rpm to a stalling point.... does this just require idle air re-learn?

ochaudhry1

the ac compressor an alternator share the same belt so if ur pully is bad it will effect ur altenator like it did mine....started off makin noise then eventually gave out and snapped the belt. I have the same pearl white 2000 maxima

maximal01

ok well heres the update it died on the way to work but then 8 hours later jumped just fine, what should my idle be at i had it around 900 at P an N and about 750 or half way between 500 and 1000 is that about right? if the idle is to low that would cause the alt to not turn fast enough?

maximal01

yes actually the steering wheel thing has bugged me forever what is the deal with it?

maximal01

ok here is the video of the lights dimming this is while im pushing the powerseat button so any thing on this? is it normal? im thinking of replacing the FL80 Main 1 & 2, what are they for?
http://www.youtube.com/watch?v=HAyf8BuUB2M

luvlexus101

iTrader: (6)

Try the wire from alternator to battery, reduced my dimming. Also I wouldn't obsess over a bit of dimming as long as the car runs fine, the car is getting older and things wont run as well as they did before. Considering when you're actually on the road your rpm is almost always about 1000 you should be fine. And changing the fuses(main) wont make a diff.

maximal01

ok well there is some corrosion on them just the 2 though

homeyclaus

iTrader: (1)

This is standard electrical troubleshooting.

You say the battery is good. Okay.

You say the alternator is good. Okay. Are you sure?

No, a failing AC compressor won't "slow the belt down" without significant noise. Think of the third thing attached to the belt: then main engine pulley, which is bolted to the crankshaft. If THAT's slowing down, then you have other issues

The belt will slip over the item with the failing bearing, or over the main crank pulley, making a lot of noise, smelling like burned rubber, and finally, it will fail. Usually in quick order.

IF alternator and battery are indeed okay, and you still get dimming lights when you run your power windows, or AC fan, there is extra resistance in the circuit somewhere:

Battery connectors are the #1 suspect - make sure they're clean, not corroded, on the battery posts as well as their connection to the cable.

Check the connection at the back of the alternator, and make sure there the alternator is well grounded (as in not mounted to a corroding mount - I have never seen it, but other members said it happened to them). Make sure the other end of the negative cable from the battery isn't corroded, or where it's mounted isn't corroded.

If it's just the power windows that cause this, I'd look to make sure that the window channels are lubed so that the motor isn't running at 150% load.