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Alternator/charging issue?

Kaput!

Active Member
Messages
279
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50
Location
BOLTON UK
Car
04 accord tourer 2.0
Hi Folks
After a long period of trouble free motoring i finally hit the buffers lol
I covered around 1k miles in her last week but towards the end of my journey i began to have issues with the 12v power sockets in car.In particular high load such as fast charging phones.Anyway i observed my outlet was intermittently dropping to around 12.4v whilst driving then after a minite or two return to a steady 14.1v as normal.There after this process continued so i suspected failed alternator/regulator so have just fitted a brand new one.
All was fine at first then five minites into my drive today it dropped to 12.5v (standing voltage) so clearly there is an issue with the output being cut or interupted from alternator at regular intervals.
Obviously i can rule out alternator as both old and brand new make no difference to issue.Car otherwise runs perfectly with pullies and belts in good order,all electricals work normally and no strange sounds or smells.Also battery is only 12 months old and is strong with a full charge at all times.
So would anyone have any advice before i try and check all wiring etc around the car etc? Perhaps there is another regulator or relay somewhere else? Really strange one this as i cant think why two perfectly good alternators would just intermittently cut supply to the whole car whilst running!
Any thoughts welcome.
K20A6 CM1
 
Many charging problems reported here turned out to be the battery that people swore was in good condition. Borrow a battery from another car for a day to rule it out.
 
I have a spare battery so i will do this to rule existing battery out.So am i right in ***uming that if you had a bad battery does the alternator cut supply to both that and the car? I ask because i am intermittently having the supply cut to the cars electrics too.ie slow wipers etc
 
Earth could also be a problem here - and an easy fix if it is that. To diagnose an earth problem you can connect a jumper lead from the negative battery terminal to the engine block for a drive. Just make sure it is clamped on very securely. It doesn't hurt to clean all the earth terminals on cars when they start to get on in age a bit.

Other possibilities - the voltage supply to the alternator. Broken soldering in the alternator Diode circuit. The alternator diode(s), corroded contacts on elements of the fuse box. I suppose you have checked other Honda forums for people with similar problems?
 
i had a very similar issue, i had a loose earth strap but that didn't fix it, so i sent mine to and auto electrician, he found corrosion in the fuse block
cleaned it out and been fine ever since
 
I'm suspecting the ELD unit in the under-hood fuse/relay box is misbehaving. It's job is to switch the alternator between low and high charging modes, ie 12.6V and 14.5V, as needed. I would say to check the G302 grounding point for corrosion, but I'm not sure where it is.sfaseafdszcs.PNG
 
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