Rep Power: 0

Ok so I recently had the alternator checked in my 03 lx coupe because at random times and in no certain situation, the lights will quickly dim and return to normal. This is done in a sort of pattern of dim dim dim normal...dim dim normal but not as if there is a draw on the alternator or anything. The honda dealership stated the alternator tested fine but mentioned something about "load dumping" that was supposed to be normal but I'm not sure I completely buy it. (and they never told me what voltage was measured during testing) The interior lights are unaffected when this happens and there's no amps or any stereo equipment in it. I couldn't find a thread about this type of thing so any info or a link to a thread would be greatly appreciated!

 
Rep Power: 518

Maybe it is normal. Charging is reduced during some low-load periods of time.....

http://hondaswap.com/ecus-electronic...s-work-524380/

 
Rep Power: 812

yup, charging goes from around 12v to around 14v all the time while driving. that 2v difference means hundreds of lumens less light from the headlights, since voltage and lumen output is exponential. it is normal and part of a gas saving feature to reduce or stop alternator charge voltage under certain conditions. also if the radiator fan is switching on and off, that can put a large load on the electrical system, which can cause dimming as well.

 
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So replacing the alternator wouldn't remedy this I'm guessing. It's just weird.

 
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Thanks for the info.

 
Rep Power: 812

no, but you could bypass the ELD (electrical load detector) so the alt is at full output all the time. it may cause unwanted side effects like worse mpg, shorter alt life, and possibly battery overcharge.

 
Rep Power: 518

Air conditioner cycling on and off, same thing.


Nope. It's a feature.


Not weird, it's just not like every other car manufacturer everyone is used to.
It's a Honda thing and has been for decades.



Here is another article to read, first item on the first page: http://dvpatel.homelinux.com/forumfiles/SN/A001200.pdf


HTH

 
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UPDATE! This morning when I went to leave for work the same dimming was happening only this time the idle was also affected and the battery light was flickering on the dash. Had the alternator check AGAIN and it in fact was the problem. It was over charging so we replaced it and it does not do any of the things it did that were supposedly "normal". This isn't me snubbing my nose to any of you, I just can't see anything normal about what my car was doing.

 
Rep Power: 518

Keep in mind that nobody here can actually SEE what your car is doing, we can only go by your descriptions.
I may have come up with something completely different if I could see it firsthand.

You mentioned the "load dumping" so I kinda ran with that.

Good you got it fixed though.

 
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I totally appreciate all the info given here and I don't want to come off as ungrateful at all. My description may have been insufficient but what you guys were saying was the same thing the adviser at the honda dealership was saying so I was prepared to accept it as just one of those things. Just happens that what may have appeared normal to the tech that tested it just happened to be a symptom of failure. I'm glad it's fixed now I just have to prepare to have my transmission fixed soon....sigh! If it ain't one thing it's another I guess!