2005 T&C Chrysler revisited.... pulsating lights

[LwnmwnMan2]

Airjer -

I know in my previous post, you mentioned that replacement of the battery will almost always take care of the pulsating.

Even if I've pretty much figured out it's when the heated seats are on that they pulsate the most??

Or is that going to bring in a different issue??

If I turn the seats on, then the lights dim in and out quickly, like the headlight you'll see on a motorcycle sometimes.

If I turn the seats off, then it goes away.

If I just turn one on, it's not as bad as when I turn both on "high".

[Jeremy airjer W]

The general rule in our shop is if the customer has a flicker complaint we start with a battery. I can't think of a time when it has not taken care of the problem but the sky is the limit when it comes to electrical quirks. I would be surprised if it didn't work and to tell ya the truth I would feel a little bad but on the bright side your starting off the winter with a new battery and clean tight terminals!

[chris63]

I've got the same problem,but the vehicle is an 85 GMC full size van.The volt meter travels around from the top range Aprox16volts to the bottom range aprox11volts.The head lights,blower motor,ect,ect all speed up and slow accordingly...............new battery will cure or is it the diodes in the alternator?????????? Any comments helpfull!Thanx.....c63

[Jeremy airjer W]

Nope, thats just one of the joys you're lucky enough to have!

[deadeye]

The alternator could also be acting up...

If you have a new battery then it would be worth taking it to get the alternator checked. The regulator controls how much current is allowed out of the alternator. If it is acting up or going bad it could give a pulsation in the headlights. take it to your local auto parts store and have the alternator (the regulator would be part of the alternator on that model) checked. any oreilly, advance, checker, autozone or napa should be able to check it free of charge. They could also check the battery while your at it.

[Jeremy airjer W]

One other thought chris. I assume this is happening when you speed up and slow down right. The higher voltage when the rpm's are up and the lower voltage at idle? If this is the case you could check to see if there is a smaller pulley available for you alternator. Smaller = more rpm's which may resolve that problem.

[Shack]

LM2,

Your concern is a tell tail sign of a failed cell/going out battery. For some reason's, the Chrysler products seem to be very sensitive about battery draw/voltage. You get a failed enough battery, you might even have to recal the ATC head.

As far as the GMC, I would go in and have a battery test, charging system test done.

Side note for F.M.ers:

Most dealerships will test batteries and charging system for free. Also right while you wait, with no appointment. This time of year, this maybe something everyone would like do take advantage of.