Mikes2000civicsi

hey guys, thought i had a engine bay wiring harness problem so i changed the whole harness with another harness in perfect working condition. Problem is, when i accelerate hard the battery light flickers on and off and my lights flicker and my subs kick off until i stay a steady speed then it all works again. Any suggestions?

jadziasman

The battery light goes on when the alternator is unable to supply enough current to keep the battery charged. That usually means the alternator is weak and needs replacement but in your case may mean your car stereo is drawing too much power and you will need an alternator with higher output (amps) to handle the load.

cjw_89

replace the alternator and install a capacitor to save it.

D Griff

Correct.

D Griff

Just to explain, a capacitor (cap) is an electrical device that holds a charge and then releases it all at once. Batteries release a charge over time via a chemical reaction, but caps can only release all in an instance. People who have amps or other electronics require more power from your car, so a cap will help when a surge is needed (like when the bass hits hard).

Mikes2000civicsi

ahh, sounds like i will be replacing the alternator, thanks for the advice, ill let you know if it works out.

itsmejto

Before you go crazy accepting advice that may not need a new expensive alternator, think of what is happening. You say it only does it when you accelerate, so I'd check for loose battery terminals first, loose connections to the main fuse, ground wires and the under dash wiring to the light itself. It could be the battery itself has loose plates in it, or even the main relay contacts (see repair manual on that one) but I very much doubt it is the alternator itself, check the heavy wiring from the alternator to the battery also, sometimes the connections work loose. Check the alternator belt itself is tight enough, sudden acceleration with a heavy load can cause the belt to slip and stop charging for a few seconds. Sounds to me like it's a mechanical problem caused by you accelerating and something is moving or loose.
Test it by turning off any loads you have, especially your lights/heater/a-c amps and see if it still happens.

Former User

^I agree. Also make sure all of the alternator mounting bolts are tight.

mechanix619

I'm having battery light issues as well. My light comes on when the car is at idle but as soon as I give it gas the light goes off.

Mikes2000civicsi

thats a very good call, i checked the battery and the connection to terminals is fine, plates seem fine, hmmm under the dash everything looks alright. maybe it is the alt belt, hmmmmmm

CivicSpoon

If you have a service manual, it will tell you how to test the alternator as well.