yaris voltage issue

[yaris2010RS]

Hey all,

Ive got this odd electrical issue and im not sure exactpy where to start. Recently ky car has had the battery light on. Upon further inspection using my obd2 scanner my ECM voltage was 11.23v. This was with idling and driving and reving. The voltage stayed at 11.23v - 11.36v until randomly the volts jumped up to 13 and 14 volts and the light turned off. This is a random issue. The capacitor on my system also displayed the same voltage as my obd2 scanner.

I would like to think this issue has something to do with my alternator having an issue but then again this issue didnt come up since after i replaced my engine and battery. So it also could be a connector or ground or something silly.

Any ideas where to start? Or possible causes?

[CTScott]

Check the terminals on the large connectors on the backside of the positive battery terminal for corrosion. Also, check the ground cables that connect to the block to ensure that you tightened them.

[yaris2010RS]

Thanks scott,

Positive terminal on the battery was fine (brand new and tight) and also my ground on the engine (that i had tons of issues due to those not being tight) are good and tight.

I did also check the main power wire from the alt to the battery and found that had been left loose....tfrom the arking it melted the plasic clip cover to protect that connection and corroided the hell out out of the screw. I tried to tighten it but due to corroision it was hard to turn so to ensure i didnt break it. I will hit it with pb blaster when i get back from the holidays and try to loosen it off, clean it and tighten the heck out of it.

Would di-electric grease be okay to put on that connector

[CTScott]

Thanks scott,

Positive terminal on the battery was fine (brand new and tight) and also my ground on the engine (that i had tons of issues due to those not being tight) are good and tight.

I did also check the main power wire from the alt to the battery and found that had been left loose....tfrom the arking it melted the plasic clip cover to protect that connection and corroided the hell out out of the screw. I tried to tighten it but due to corroision it was hard to turn so to ensure i didnt break it. I will hit it with pb blaster when i get back from the holidays and try to loosen it off, clean it and tighten the heck out of it.

Would di-electric grease be okay to put on that connector

Dielectric grease won't hurt it.

[yaris2010RS]

Ugh.... so as predicted the stud broke....... is there a way to remove the old stud from the alt or do i need a new one ?

[CTScott]

Ugh.... so as predicted the stud broke....... is there a way to remove the old stud from the alt or do i need a new one ?

The way that the bolts snap off they are typically easily removed, once you get the alternator off. Crashy2's snapped off as you see in the picture below. Once it broke I was able to work the alternator off of the mount and then was able to get the broken piece out with a drill and an easy-out. Use a liberal amount of never-seize when installing the new one to prevent the same problem in the future.

http://i372.photobucket.com/albums/oo163/ctscott329/Crashy%202/Alternator.jpg

[WeeYari]

My take on this is he broke the brass stud that the 12v cable connects to.

[CTScott]

My take on this is he broke the brass stud that the 12v cable connects to.

If that is the case, then it can be repaired by replacing the rectifier assembly, which it is part of:

http://i372.photobucket.com/albums/oo163/ctscott329/Yaris%20-%20Alternator/ALT-CoverOff.jpg

http://i372.photobucket.com/albums/oo163/ctscott329/Yaris%20-%20Alternator/ALT-RecBottom.jpg

[yaris2010RS]

That is really disappointing.....

For now Im gonna try to make shift something.....

Thanks guys

[yaris2010RS]

Hey scott, by any chance do you have part number for that? i managed to make it work for now but its a tempory fix for sure

[CTScott]

Hey scott, by any chance do you have part number for that? i managed to make it work for now but its a tempory fix for sure

27357-22200

[yaris2010RS]

you are GOD my friend

and the loose and corrodied connection there does appear to have been my voltage issue