Car lights and electricals randomly dim when I am stopped.?

I would take your car to a mechanic to get a diagnostic on the transmission/torque converter. When you come to a stop, your torque converter should automatically remove the load from the transmission. If it is going bad, the transmission will keep a load on the engine (which has idled down and is not creating as much power as when you are driving) and it will cause your engine to labor (slow down). If your engine slows down, your alternator won't create as much power and could potentially cause your lights to dim.

Also, just to make sure, check to make sure that your alternator pulley (or other pulleys) aren't getting stuck. I would look at the torque converter, first.

Sounds like a low idle speed. If you have a tachometer you should see at least 800 RPM. If it's lower than that then it's possible the alternator just isn't spinning enough.

You mention new battery and alternator - OK, assuming they are good, you mention no corrosion or fouling. OK, assuming the terminals are clean. ARE THEY TIGHT? If they're loose you can get similar conditions as you describe.

Hope this helps.

'av'a g'day mate.

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ADDITIONAL: J. J. mentions the alternator belt. More so if the belt was slipping the battery would not be charging properly. But that would manifest itself at higher RPM's than at idle. Power is a function of mechanical energy (the engine turning) and voltage. At lower voltages (alternator spinning at idle) the power it produces is diminished. Hence, a lower production of power requires a lower amount of mechanical energy. At idle the belt is less likely to slip. Nevertheless, J. J.'s advice to check the belt IS a good one. I have a 2003 Hyundai Sonata (four cyl.) and am constantly battling slipping belts. Don't tighten them enough and they squeal when cold. Over-tighten them and you ruin bearings and have to replace components.

But I think more likely is that you may have a bad connector or bad ground. Not TOTALLY bad, but going. The problem will only get worse. (assuming a bad connection)

Here's the thing: If the battery is properly charged then at idle, when the alternator is not producing as much power, the battery will carry the load. If not - then at idle the lights depend solely upon the alternator. Assuming the system is idling properly (I have idle issues with my Hyundai) and the lights are dimming then the battery is not getting fully charged. This is what makes J. J.'s advice valid; if the belt is slipping the battery won't charge properly. But since you said these things are new I'll assume the alternator is not slipping (though it may be). That being the case it leads me to suspect a loose connection.

Let me know what you find.

To check the alternator belt, with the engine SHUT OFF (I have to say it that way - no telling WHO will try this with the engine running) see if you can turn the alternator by hand. You may need a wrench. Turn the alternator. If the belt is loose it will slip. If the belt is tight enough the whole engine will turn. So if you turn the whole engine then it's NOT the belt. If it DOES slip - tighten it and see how things perform after that.

If the belt is not loose (as I suspect) check the battery terminals for tightness.

Hope this helps.

'av'a g'day mate.

")

@ Chris: Torque converters are designed to slip. At low speeds the converter is slipping. At higher engine RPM's the torque converter goes into full lockup (to prevent loss of mileage due to slippage).

Could be as simple as the alternator belt in not tight and is slipping at idle because of the load. That would be the first thing I'd look at and if it is not that then your alternator is not working properly, for that you need a load test put on the battery when the car is idling.

If by using vehicle mild, you mean your headlights, then yes, the interiors lights will get somewhat dimmer. Your battery may not be working at height efficiency. In case your battery isn't providing you with challenge proper now, and if it is 4 years or older, bear in mind buying a new one whilst that you could seize one on sale. It is constantly good insurance. You don't want to be stranded somewhere or have to pay for a new one at a gas station on the freeway.

I have a Chevy Cavalier and mine was doing the same thing when the negative wires and connections got loose by my starter.

Are you running the A/C or Defroster? Sounds to me like the compressor is running.