So my battery isn't charging so i took my alternator to pepboys to get checked out and they said it was fine..so i just put it back in and its not charging the battery...and i got a little alternator test light thing from them and says its only 12.0 volts on the battery terminals...but i know it should be 13.0 volts or up....so im confused as to why out of no where it stopped working...thanks.

 

Is the alternator fuse blown?

Are the alternator connections clean and tight?

 

You need to have power on one of the small wires with the key on to activate the alternator. It should be labeled "I" and I think it is yellow and black. If it's a '96 to '98 model this wire is known to short out behind the engine and blow fuse #15 under the dash.

Also check the big fuses in the underhood fuse box.

 

well fixed the alternator problem...i decided to fix all my fuses from the guy before me and some how it works now...but i still have some other problems...I don't have vtec anymore and my car is idling at 2500 rpms..would either of those be because my alternator is in high output mode trying to charge the battery and cuts of all auxillary ports or something? thanks

 

No that's another problem. The ECU can do a couple of things to the alternator, but the only time idle speed is increased is for the A/C.

The idle is increased when the engine is cold, or the ECU thinks it is cold because the coolant temperature sensor is bad. If it is fully warmed up and going into closed loop, any vacuum leak will still make it idle too high.

Whenever the CEL is on for any reason, VTEC will be disabled.

 

ok but the CEL isn' t on...so i dunno about that...i checked the wires going to it and looked fine...i couldn't really tell if there was a vacuum leak..didn't hear any odd noises...but thanks..

 

What was the alternator fix? What fuses were blown? What year Civic?

Does the CEL work?

 

Well the guy that had the car before me had all the fuses mixed up with wrong amps...so i fixed that problem and used all new fuses...none of the fuses were blown though...and the CEL does work... and its a 96 ex with a B16 A JDM engine...thanks