Austarion

hi, i question pls. i got this problem since last week, my car voltage keep going low when switch on accesories like a/c, radio, headlight, etc .. when the car at idle without switch on accesories the volt meter inside car reading is 13.7 volt but when switch on all the reading will going lower to 12volt sometime to 11.6volt. then i checked at the alternator output with multimeter when all the accesories on the reading is 14.1volt and with all accesories off the reading is 14.7volt. and the volt reading at battery terminal is 12volt all on and its not charging the battery.
is it a alternator problem or wiring problem? (sorry for bad english )

thanks

Clean everything you can unplug first! Use sandpaper or small file to remove oxidisation and use contact cleaner or at least wd40. Make sure all battery leads and terminals are clean. Even if they look fine, use a wire brush, sandpaper to go over them.

Then see if the situation improves

thanks bro, will try that, is this anything to do if my battery r relocated at trunk?

You need heavy leads as there will be too much voltage drop if you have thin leads.

Pay particular attention to your grounds. Do you have a good solid ground lead from your engine to the chassis?

The fat wire from the alternator or one of the connections along it is the problem.

thanks all for the reply, found the problem , its a fat wire from the alternator that give the problem, all copper inside already correded , change it all to thicker lead (8awg) from output of the alternator to distribution box and to the battery terminal improved everything. thanks all again for the trouble shooting suggestion and redzone ,i still owe you nasi kandar :D

p/s: i got a complete set of VELNAS unit come with the wiring harness but faulty display (the clock unit) . if anyone need it let me know ,i give it F.O.C