2012 Honda Civic EX - Alternator only charges when the headligts are ON

[vancto]

Hello all,

My Honda civic 2012 EX's alternator only works when the headlines are ON.

Voltmeter said my battery is 12.4 V. I turned on the car with headlights OFF, it's still 12.4 V (indication of alternator NOT charging/working).

But as soon as I turn ON the headlights, I get 14.5 V.

Has anyone seen this before? and what did you do to resolve this issue?

Thanks for your help.

 

[Esotericimage]

The alt doesnt charge all the time. when theres a load on the system it will charge past a certain RPM or under load.. This is normal. Read up on ELD functionality

put your voltmeter away.

 

[vancto]

The alt doesnt charge all the time. when theres a load on the system it will charge past a certain RPM or under load.. This is normal. Read up on ELD functionality

put your voltmeter away.

Esotericimage, thanks for your post and I agreed with you that alt does not charge all the time.
2 weeks ago, my civic did not start. I jumped it, it started right away. Took it to Autozone to test the battery. Battery is good
It started fine for 2 weeks but just yesterday, it failed to start again. I jumped it, it started right away. Took it to Autozone to test the battery, battery is good. Also asked them to test the alternator. Result: alternator is good when headlights are on; and alternator is bad when headlights are off.

 

[Esotericimage]

Sounds like an ELD issue..