So I'm fixing up my honda but I keep having a problem with my headlights dimming and dash lights dimming while accelerating as rpms go up it dims but brightens once I press clutch it's fine while ideling but once I start driving they cslowly grow dimmer and air system in car is effected to i have already replaced battery terminals done a big three bare metal connection replaced alt with 130amp one with 4 guage wire running to positive post in addition to charging wire one done both belts checked battery runs 12.5 off aprox and 14.25 while one I also wire brushed the fuse panel main contacts eld replaced idk what is causing it any ideas would help

also this problem started before any of this work was done everything I've done has helped problem but hasn't solved it wondering if it could be a trans ground or battery crank amps are bad or somethingLast edited by Grumpy pigeon; 03-24-2017 at 01:55 PM.

 

Update

replace my transmission ground and grinder bare metal really easy with a wire brush attachment and drill lights no longer dim or if so barely noticeable and my engine is running much better seems to go faster at same rpm and clutch pedal is firmer interestingly enough not sure how but definitely noticeable difference would also like mention my grounds were decaying away and rusty I plan to run another wire from grounding location of trans to negative battery terminal and also ground alt to chassis all 4 guage

 

So spoke to soon lights still dimming wondering if clogged cat can be doing it cause it preforming better when light off if anyone sees this and has a slight clue lemme kno

 

First thing I would check is battery voltage when running. Could be your alternator is weak and just not producing enough charge when under load.

 

I had the same problem I had to replace the alternator and the ELD

 

Well I've checked it while running and have a rebuilt alternator I should check while under heavy loads but it's a 130 amp alternator

I have already done both of those could it be my battery voltage is fine running 14.2ish and like 12.5 off but I've heard crank amps can go bad without voltage problems

 

So update for anyone who cares I replaced relays for headlights and they don't dim anymore dash lights still dim but can't find any type of relay for dash lights also checked cluster circuit board but looked completely fine and the led bulbs in my cluster keep burning out all very dim except odometer display will replace blinker/ headlights switch

 

Interesting result - I thought when a relay goes bad it would be an intermittent failure as opposed to a gradual degradation over time. I learned something today!

 

Ive heard of the drl dimming from relays but not headlights. Interesting tho! keep us updated

 

As soon as I get paid I'm getting a new switch after that I think I'm tracings wire if it's not fixed I have noticed a slight dim in the headlights every once in a good while but not the same symptoms as before it doesn't relate to rpms and my just be from fan or other components flipping on

Very mild and probably only noticeable because I'm looking for it