Well i was having a problem with my charging and brake little coming on. I know that this normally is the alternator is causeing the problem. So i have gotten the alternator tested and it passed. I have replaced the battery and now the charge light is out but the volt well running is still only 12v. I have checked all of the grounding point for both the alternator and battery. Well the truck is running i have disconnected the alternator plug on the drivers side fender and checked all of the wires coming from the plug on the alternator. It looks to be that there is no power coming thru these wires. The white, black and the yellow and there is no power. I am wondering if anyone has had this problem? and if its just as simple as i need to replace this section of wiring. \

Thanks.

 

You may have a bad connection on the plug at the alternator, or as you suspect a bad section of wire... what you need to do is run a continuity test on each wire between the alternator plug and the fender this will tell you if you have a bad harness or not....

 

Sounds like you're getting a lot of odd readings from your voltmeter; you may wanna check it against a known reference (make sure it's working properly) before you start checking things....may save you a lot of headache.

 

i had the same problem. charge light and brake light on at same time. had the alternator tested and it passed. hooked it all back up and seemed to work. next day it came all back on. went and bought new alternator and new battery cables and seemed to have fixed the problem. just my 2 cents

 

great post 4runna lots of great info and pics...