So I replaced the alternator on my 2005 Honda Civic, LX Special Edition, Auto, with 1.7 L, as I was told it was bad. Drove the car for 20 minutes and it died. Jump started car, got it home and replaced the battery. Drove it for 20-25 minutes and it died. Jump started it to drive it home. Any ideas why this is still dying after driving it for 20-25 mins? I also replaced the battery as it was believed it was bad also. Drove it for 20-25 minutes and it died

 

I know you just bought the Alternator but you may want to check if it's faulty. I've seen cases where the "new" alternator is defective. Whether the alternator is a reman or new. Are any of the lights on when this occurs? Battery light, check engine, etc...? I know when mine went out all of the lights were flashing and were dimming pretty bad.

 

also be aware that this is a ECU/PCM controlled alternator and if the alt goes bad it can damage the ECU . so your new alt seems to not work ,there is a TSB about this happening usually happens after T-belt is changed and the Alt bolts are left loose ,Alt is damaged due to poor grounding and it takes out the ECU control circuit.

just a heads up if all other testing indicates everything is ok you might have this occuring

 

If under-dash Fuse No. 4 (10A) is blown or there is an issue with IG wire (Blk/Orn to Blk/Yel wire), then the alternator won't charge. Fuse No. 4 and the IG wire supplies the ignition input that turns on the alternator/regulator assembly. So, check the fuse and the wiring too.

 

Okay, so now I replaced the alternator with a new alternator. Now the battery light is on and it shows 15.8v when the engine is running. Is this another bad alternator with a bad regulator??? HELP????

 

your alternator is over charging. if you continue to run it like that you could damage all circuits in the car, without blowing any fuses.

the higher you rev the car the higher the volts will climb...

it happened to me and the first thing that blew was the brand new 3 day old headlights. fuses did not blow in my case.

yes it is another bad alternator!!!

 

i would shop at a different parts store