FilPilot

I have noticed recently that my headlights dim for a split second as soon as I hit the brakes then they go back to normal.

I sanded the paint down to bare metal, applied a little dielectric grease and reinstalled the ground wires. also battery terminals. Check Batt and charging 13vdc all ok...

Any one else has this problem? any ideas on fixing it?

Should I install LED lamps? less current draw.

thank you in advance

richee3

Could be the alternator starting to fail, or possibly the battery is too small.

salimshah

I think it is normal. You can have the vehicle tested at an autopart store, usually at no charge.

Salim

walkerman

I noticed that recently on my 2001. I also noticed that the lights were flickering at a steady rpm. I put a voltmeter on the battery and the voltage was jumping up and down between 13.8 and 14.7. Sounds like alternator time soon......

FilPilot

Tested the system today on the way home from work. it would seem that the headlights are not dimming anymore

Also would like to mention that..I cleaned both terminals and added some Magnesium Sulfate (epsom salt) with distiled water to the battery and charged it for about 2 hours at 40 amps.

Thank everyone for the input. I will keep an eye out for the alternator/battery and update this thread if anything changes.

FilPilot

OK no more dimming / flickering of the headlights, however now after starting vehicle and turning the overhead light on, it flickers. Maybe as some folks have mentioned the alternator/regulator fluctuating means it is starting to go

salimshah

Woa! Where did you hear about adding epsom salt? And 40Amps of charging current?

Salim

FilPilot

where else.....the internet

salimshah

Dont believe everything you read on the internet! Some of it can be disastrous with serious and permanent disfigurement (acid burn in this case).

Suffice is to state that if you charger shows more than 5 Amps after 30 seconds disconnect and take your battery to a professional. (12Vx40Amps= 480Watts .. which can boil the electrolyte)

Maybe a chemistry major can fill this out ..

H2SO4 + Epsom Salt + H2 + O2 --- heat + emf --> ??

Till that time nothing should go down in the battery other than H2O. [This is what is specified by battery manufacturers]

Salim

FilPilot

Just an update all is well, temps in Virginia have dropped down to 20s battery is holding up and the car starts up well. lights still show some dimming. when applying brake lights.

FilPilot

Just an update. I am still experiencing the same dimming problem. since last post.
New battery, same alternator.

Has anyone installed a large cap so as to stabilize the current spikes?

kalali

Fluctuations in voltage are normally a sign of a marginal voltage regulator.

DeadRX

Mine has being doing this for years... More noticeably, the interior overhead lights when you open the door do it as well at night. Must just be alternator on it's way... ugh whatever...

salimshah

In pursuit of perfection ....

Dimming is normal. The sources (alternator and battery) and wires are non-ideal and when substantial load is dumped on, there will be less juice for the headlights.

Salim