Best Answer
1The same thing happened to my Buick Regal, and I had to replace the alternator. Eventually the car started cutting out when using the cruise control. 2I had the same problem with a 1991 Lincoln and a 1995 Lincoln, and it turned out to be the voltage regulator 3Sounds like your alternator is buggered mate. If possible, have a mechanic check the amount of volts being produced by your alternator. If your alternator is not putting out 13.5 to 14.2 volts, your voltage regulator MAY be bad. Most newer cars now have the voltage regulator built into the alternator, which means replacing [or overhauling] the alternator IF the regulator is bad. 4, Additional ConsiderationsWhile answers 1 through 3 are correct, alternator and/or regulator failure/defects ARE NOT the only cause of "pulsing," flickering, and/or dimming of vehicle lights.

There are probably several other causes, but I can only think of two others right now:

[1] This condition usually occurs when the engine is IDLING, and often is caused by the IDLE SPEED being TOO LOW.

[2] 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.

User Avatar

Wiki User

βˆ™ 2015-07-17 17:45:18
This answer is:
User Avatar
Study guides

Add your answer:

Earn +20 pts
Q: What causes the headlights dashlights radio and dome light to pulse with the engine running?
Write your answer...
Still have questions?
magnify glass
Related questions

How do you turn the headlights and running lights off while keeping the engine running?

Try applying parking brake

Do automatic headlights come on when 2002 Chrysler 300 is started?

Auto headlights come on when it is dark. Daytime running lights are on whenever the engine is on. Both are optional equipment.

How do you turn off the headlights while the engine is running on a 2003 Toyota Tundra?

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.

What is the amount of voltage for a Mercury Sable alternator?

13.8 - 14.4 volts DC,13.82 with engine running and headlights on!

Does having headlights on during the day use more fuel?

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,

How do you no if the Alternator 1999 Honda CR-V is bad?

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 is the valve timing on a Mazda t3500 engine?

what causes aknocking sound on mazda T35 engine when its running

How do you turn off 1999 buick regal headlights while car is running?

push the parking brake ,before starting the engine

What would cause the headlights and interior lights to fade on your Chevy Venture?

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!

How do you turn off headlights on a 1999 F250 Ford while engine is running?

I take it you have daytime running lights , if so by engaging the emergency / parking brake the daytime running lights should go off

What Causes sitting in the car for more than 2 hours with an engine running?


What is causes engine to knock and shake on gmc jimmy running with no oil?

The lack of oil?!?

People also asked