Hello, I'm new to this forum and to the Civicwe now have. I picked it up cheap for a father son project. It wouldn't start. First things we replaced were the coil and igniter, now it starts and runs well but the battery and ABS lights are on. I went through the steps in the manual we have, I have listed them below.
-check all connections- good
-pull the plug on the alternator, the battery llight should go out- also good and the ABS light goes out but not when the plug is in (bad alternator making the ABS light go on???)
-check the voltage with car running - ok, around 14.5 volts
I also went as far and pulling the ground while the car is running, the voltage jumps to 15.6 or so. My Odyssey does not do this so I'm thinking it's the voltage regulator. Any thoughts because it's pricey to replace the alternator.

thanks,
Mike

 

You can purchase a rebuilt alternator with a lifetime warranty for about $100 from AutoZone.

The service manual details how to retrieve the ABS trouble code:

http://hondatech.info/downloads/Auto/Manuals/Civic/

 

If your running voltage is 14.5 volts, I do not suspect your alternator. As long as it's above 14 V, it should be good. Only way to know for sure is to take it out and bench test it. Normally they don't do this unless it already shows signs of problems. take it to an autoparts store and have them check it out but it doesn't sound like a problem to me.

not sure about the voltage regulator. check the abs codes first b/4 messing with the alt.

 

It's possible to have a bad alternator that keeps the light on but otherwise charges OK. This function is controlled by the regulator. The regulator is inside the back section of the alternator. It is the plastic part that includes the socket the wire harness plugs into. It can be replaced seperately if you can find where to buy one.

Never ever disconnect the battery with the engine running. Just wanted to mention that. To test an alternator start the engine, turn the headlights on so there is some load, and measure the battery voltage.

 

Thanks for the replies. I did jumper the connector to find an ABS code and got none. The only time the light will go out like it should is if the alternator plug is disconnected which seems odd to me (just turning the key, not starting). I'd rather not buy a new alternator if that is not the problem but seeing it jumps over 15 volts with the battery disco'd I'm thinking the regulator is bad, again my Ody does not do this and it's a similar setup. Just checking the voltage with all lights on show it ok but does not mean it's not an over voltage issue. I may remove it and bring it to a store to test it. mk378, I've removed ground terminals off a battery while a car is running many times in the past 25 years I've been messing with cars, what have you seen happen?

 

Yep, ignore the ABS light until you fix the alternator because the service manual states that:



Typically, the battery/charge light indicates a problem with the alternator. One exception is if you have an electrical short in the BLU/WHT wire leading to the voltage regulator.

 

Yes get the basic electrical system working before looking at trouble codes. Squirrley battery power can also cause a lot of false check engine lights and ECU codes.

 

I've always been told when the light comes on it is either the battery, alternator or voltage regulator. You can also add a slipping altbelt to that.

For me it has always been the battery and sometimes the alt but they usually fail at highway speeds not starting and the battery fails at starting.

The alt may have several leads off it at different voltages and you could ckeck it according to spec. The same for the voltage regulator.

I would clean and check the connections to the battery very very closely....

 

Everything I checked pointed to the alternator. These little beasts are expensive new or rebuilt. I bought one off E-bay delivered to my door for $60. Was pretty easy to swap and now the battery and ABS light go out like they should. Thanks for the help.

Mike