Hey everyone, good day! I have a question, that I couldn't find a for sure answer searching the forum for. My headlights seem to flicker/get dim when my brakes are applied, or when I take my foot off the gas to slow down. My alternator has also been making a sporadic "grinding" noise when the car is cold. Any ideas if the 2 problems go hand in hand? Is my alternator going/has gone bad?

I appreciate all your help in advance. Its a 96 ES300 BTW. All help is appreciated.

 

When the battery was near gone on my Cadillac everything would die (dash cluster, headlights, interior lighting etc.) when I applied the brakes. The strain of lighting up the brake lights was too much for the old battery. Replaced it with a die hard from Sears and everything has worked properly since.

 

Our 94 ES has done this for the entire 16+ years that we have owned the car. We are on probably our fifth battery, and installation of a new battery has never made any difference.

The independent mechanic who does the repair work that I don't wish to tackle says it is likely a grounding problem, but he has never been able to isolate where the problem lies.

I consider this just a nuisance, not a problem.

 

Happens to my 96 es300..but doesn't bother me enough for me to tackle it at the moment

 

Is the alternator belt loose/worn?

 

The alternator belt is worn. Just replaced the alt belt and PS belt this morning. The lights still dim etc. The alternator still makes a sporatic "grinding" sound when cold. For example, when my blinker is on, I can see the CC light get dim the bright then dim with the tick of the turn signal.. Should I have the alt tested? My battery is less than a year old. Any thoughts?? Thanks for the input. I appreciate it.

 

It can't hurt to get your battery and alternator checked out by somebody reputable, but I'm betting you have a bad ground somewhere. I have a similar problem with my 2000 ES300 Platinum that I believe is also a bad ground. At night - in park - at idle the interior lights flicker when I turn them on and revving the car doesn't change anything. I haven't spent any time tracking down the bad ground. Anyone else had this problem and found the cure?

 

Is there a schematic or something that shows where all the grounds on the ES are?? Anyone?

 

My '98 does the same thing at idle, headlights/taillights/interior lights all flicker at the same frequency. Haven't investigated it yet though.

 

is it oem alternator. bad alternator might cause this flickering.

 

If it's the alternator revving the engine a little should stop the flickering. In my case revving the engine doesn't help. That's why I believe my problem is a bad ground somewhere.

 

I don't think it is the alternator either. My alternator just died last week and my lights would do the same thing that yours are doing right now even after getting my alt rebuilt and getting a new battery.

But did you check how much power the alt is putting out? It might be worth checking. It should be in the 14s somewhere.

The noise is probably from the alternator bearings.

 

alternator tested, new belts installed, lights just dim etc now. Looks like its just an annoyance I will have to live with. ugh.. oh well. what do you expect from a 14 yr old car right?? lol. Thanks for all the help. The noise isnt there with the new belts so thats good.

 

have you tried upgrading to a 100 amp alternator eg highlander alt. other forum points to initial o2 sensor ecm triggers that causes flashing.

 

To put it as simple as possible the stock 80amp alternator isn't strong enough to support the vehicals electrical needs. Lexus/Toyota decided to overlook this as just an annoyance and not a real problem. this is the last gen es with an 80 amp alt.. starting 2002 they used 100amp alts. the only solution is to upgrade your alternater. the 2001 toyota avalon is a direct fit and its 100 amps. so is the toyota highlander 2001. 100 or 130 amp. this will fix your flickering lights