2004 civic lx 148k miles- Replaced battery and alternator. Alternator showing 12-14v at alternator post. Battery not seeing those same volts. Grounds all look good and wire doesnt appear to be nicked or damaged. Should be getting same voltage at T101, but not. What could be acting to pull down voltage? Also cant get obdii to connect.. maybe coincidence, but believe its part of same issue. Car runs well when battery fully charged.

 

Hi,
Did you do a "drop test" with a VOM on your connecting cables???

IF your Alt. is putting out, but it is not getting to battery???

 

i actually didnt know how to do a drop test, but i took the car after charging the battery to autozone and had them check the alternator (which was brand new). The guy with his tester immediately said- ooh.. bad voltage regulator.. so, thanks for the feedback- bad ‘rebuilt’ alrernator from Autozone… got a new one, installed and now maintains charge! Situation resolved!

 

dang wish I had the same situation, someone went through my car turned the lights on and I jumped it and after that it was not right, gauges were cutting out and car wouldn't shift, tested at autozone bad VR and then got a reman. It worked for a day then ww went to autzone they said bad VR on that so we went totally brand new duralast, and it worked for 1 day and then you use AC or anything gauges cut out and act the same way we took out the alternator again had it bench tested and it actually tested good, and this is after also replacing the battery aswell because a shop said battery could've been bad because it died alot even though it was a year old. I would've went OEM honda but they want 1200 for brand new and 580 for reman..