There are probably several other causes, but I can only think of two others right now:
 This condition usually occurs when the engine is IDLING, and often is caused by the IDLE SPEED being TOO LOW.
 Slipping of the belt and/or pulley which drives the alternator can cause the same symptoms.
I suggest that you have a PROFESSIONAL AUTO ELECTRICAL TECHNICIAN, or any PROFESSIONAL [and well experienced] auto mechanic, check your problem out, and PROPERLY ADJUST the idle speed BEFORE any consideration of replacing an alternator and/or a voltage regulator.
If you simply replace these expensive components, AND THEY WERE NOT At Fault, then you will have WASTED a lot of money, AND you will STILL HAVE the problem, with more expense to come.
. Good luck.
Try applying parking brake
If you are parked with the motor running, engage the parking/emergency brake. Turn the ignition off and restart the engine. The daytime running lights should not be on.
Auto headlights come on when it is dark. Daytime running lights are on whenever the engine is on. Both are optional equipment.
no, using your headlights during the day, just uses power from the battery, and not from the engine, the battery is constantly being recharged , while the engine is running, any way,
13.8 - 14.4 volts DC,13.82 with engine running and headlights on!
If you have a voltmeter, measure the voltage across the battery, with the engine running. It should measure around 13 -15 volt (alternator is ok) now turn the engine off it should measure 12volt. If you do not have a voltmeter ,let a friend watch your headlights at night with engine running,than turn engine off, your headlights should go dimmer with engine off.
what causes aknocking sound on mazda T35 engine when its running
push the parking brake ,before starting the engine
If the engine isn't running, the battery is low. If the engine is running, the alternator probably has a problem. If you are wearing dark sunglasses, remove them and the lights will get brighter. good luck!
I take it you have daytime running lights , if so by engaging the emergency / parking brake the daytime running lights should go off
Your question is sort of backwards, perhaps you meant what causes engine failure? Engine failure causes...the engine to fail. If someone told me their engine failed I would take it to mean that it stopped running, or wouldn't start.
The lack of oil?!?
radiator fans running to cool engine...
Dim headlights, Flickering headlights, Starter sounds sluggish when cranking, Battery light comes on or flickers, Voltmeter drops below 13 volts with engine running,
When you turn on the headlights of any car it causes a load (or horsepower drag) on the engine. Your car has an idle problem and the load on the alternator simply exacerbates it.
The engine is not running!
It is very simple in between your engine head uner your headlights you should see you canble running to it
Because the power for your headlights is pulled from your battery. When the dashboard lights dim after turning on the headlights the dashboard lights aren't getting as much power as they were with the headlights off. With the motor running or off? The headlights draw a lot of current, but should not visibly affect other systems. There could be a problem with a worn out battery, an alternator that isn't charging correctly, or you have a bad earth between the battery and the chassis. Check the large cable connection between the battery (usually negative these days) and the bodywork, or between the engine block and the bodywork.
Removing the oil cap with the engine running causes a vacuum leak in the positive crankcase ventilation. This causes too much air to enter the cylinders at once, which results in a stalling engine.
An alternator is the part of an automobile that generates the power to run the radio, headlights, speakers, and air conditioning as well as any other electronic component in the car while the engine is running. This is different from when the engine is not running. When the engine is not running, the 12 Volt car battery operates these electronics. Unfortunately, every battery will die eventually, so the alternator also recharges the battery while the engine is running. This is a slow process, though. But unless the battery is charged, the engine usually can't ever be started.
when i am driving my toyato 2001 Eaco stops running, it will start back up
You may see the headlights and dash lights flicker at an idle. You may hear unusual noises coming from the alternator when the engine is running.
what is the running mate in engine