Change BLK/OR wire from alternator

[mistert2]

Does engine need to be on?

 

[mistert2]

Yes I checked wiring diagram. big help thanks

 

[koda2000]

yes the engine needs to be running to check the voltage with the jumper cables connected. you can put the cables on while the engine is running. just be careful.

 

[mistert2]

WOW koda2000 I mean it you are somethin. Ran battery cable to positive on battery and lrg nut on top of alternator and am getting 14+- volts at battery and ck battery light is off in vehicle. What does that tell you /me. whats bad? I am soooo excited.

 

[koda2000]

ok, now we getting somewhere... try it with just te negative cable. if it still shows 14v then we know you have a ground problem. if goes back to NOT charging then we have to keep looking at the positive side. try it with just the positive jumper cable.

 

[albi1cnobi1]

Thats where I was going when I suggested the new wire from the alt to the fuse. Except I was taking it one piece at a time. That is telling us that somewhere in the wiring between the battery and the alt you have a problem. Either a bad connection or a bad wire. There are only 3 things between the battery and the alt. A cable from the battery and the 175 amp fuse, the fuse itself, and a cable from the fuse to the alt. Somewhere in there lies your problem.

Edit: Sorry about that koda. I guess you type a little faster than me. lol

 

[koda2000]

Thats where I was going when I suggested the new wire from the alt to the fuse. Except I was taking it one piece at a time. That is telling us that somewhere in the wiring between the battery and the alt you have a problem. Either a bad connection or a bad wire. There are only 3 things between the battery and the alt. A cable from the battery and the 175 amp fuse, the fuse itself, and a cable from the fuse to the alt. Somewhere in there lies your problem.

Edit: Sorry about that koda. I guess you type a little faster than me. lol

that's okay. the weather here is terrible and my internet speed has taken a massive dump. very frustrating... am i wrong or did the OP tell us he was only getting 10-11 volts at the alt B+ terminal? if so the problem may be on the ground side.

 

[mistert2]

Ok negative battery to body of alternator back to 12.4v.

 

[koda2000]

Ok negative battery to body of alternator back to 12.4v.

okay. now positive only?

 

[mistert2]

positive only charging 14.0+-v... woohoo.

 

[koda2000]

okay, great! so we know the alternator works and that there is some kind of problem with the B+ wire's path back to the battery. by using the positive jumper cable what we did was to bypass all the stuff (connectors, wires, fuses) between the alt and the battery. go back to the wiring diagram and check each component one at a time until you figure out where the failure is.

edit: don't forget to check the yellow/white wire at the alternator

 

[koda2000]

okay, great! so we know the alternator works and that there is some kind of problem with the B+ wire's path back to the battery. by using the positive jumper cable what we did was to bypass all the stuff (connectors, wires, fuses) between the alt and the battery. go back to the wiring diagram and check each component one at a time until you figure out where the failure is.

edit: don't forget to check the yellow/white wire at the alternator

don't be afraid to jump the 30A and 175A MEGA fuses to eleminate them from the equation, as we know we're dealing with any shorts.

 

[mistert2]

checked schematic and best I can figur after chkg is
BLK/OG wire good, ran new wire fm B+ to dist box and reads 12.6v
30 amp mini good
50 amp maxi good
175amp mega ??? shows continuity but (can I jump this with a jumper?)

anything I missed?

I'll see if I can send schematic

 

[albi1cnobi1]

Here you go.

It's not that uncommon for the connection at the battery terminal to be bad. But as you can see by the diagram there is only 3 things in line on the positive side. Try this, take your jumper cable from the B+ on the alt to the side of the mega fusae that hase the blk/or wire on it. If not charging, move it to the other side of the fuse. If its charging the fuse is bad, if not move the cable to the positive battery term again to double check. If charging the wire from the battery to the mega fuse is bad.

 

[mistert2]

This should be it


http://i777.photobucket.com/albums/yy57/albi1cnobi1/185184138_zps0e0b459e.gif

 

[mistert2]

thanks

 

[koda2000]

This should be it


http://i777.photobucket.com/albums/yy57/albi1cnobi1/185184138_zps0e0b459e.gif

yes, you can jump the mega fuse, and jump the 30A fuse that is between the blk/or and yel/wht wires. if nothing changes, jump the yel/wht wire back to the alt.

 

[albi1cnobi1]

That 30a mini gets its 12v from the battery through the same feed as the B+ of the alt. If that mega fuse isn't getting the correct voltage neither the B+ or the field will do its part in charging.

 

[mistert2]

How do you spell SUCCESS.
I jumped mega fuse 175a and bingo I have 14.4v at battery charging and chg battery light is out on dash.

YOU GUYS ARE AWESOME!!!!! THANK YOU SOOOOOO MUCH

 

[albi1cnobi1]

Congratulations. Good job, awesome that you figured it out. I would put money on the fact that at some point during the starter work or alt change outs that positive wire touched ground and blew that fuse. The sweet smell of success. Now just pick up a new fuse and you're home free.