Wiring help with HO Alternator Please!!

[Yaris Lighter]

I just received an HO Alternator today and it has only three wires. I'm trying to figure out how to turn the wiring for the old Volt. Regulator four wires into three wires.
I have found a diagram in the Toyota Wiring Manual but I don’t want to mess up (Plus I don't even know if it's the right diagram).
From what I'm guessing so far is this:
HOA's Blue "S" wire to Plug's white wire
HOA's Green "Ing" wire to Plug's Green wire
HOA's Yellow "L" wire to Plug's Blue wire
But I don't know what to do with the Pink wire
If someone can take a look and tell me their inputs; I would really appreciate it! Thank you for all your time!

http://i151.photobucket.com/albums/s149/ahdefjjk5/20121115_165401.jpg
http://i151.photobucket.com/albums/s149/ahdefjjk5/20121115_175651.jpg
http://i151.photobucket.com/albums/s149/ahdefjjk5/Wiring.jpg

[CTScott]

So, the HO doesn't have the pink "M" wire? That wire goes to the ECM and the A/C ECU as a signal that tells them if the alternator is outputting power, so they know if it is OK to run various high current functions.

In your case, you would now just cap that pink wire off.

[Yaris Lighter]

So, the HO doesn't have the pink "M" wire? That wire goes to the ECM and the A/C ECU as a signal that tells them if the alternator is outputting power, so they know if it is OK to run various high current functions.

In your case, you would now just cap that pink wire off.

Thank you so for your reply Scott! I shall do just that!
But I just want to double check.
Will I then have a problem with the ECM and A/C ECU not receiving that signal or will it not really effect anything worth worrying about?

[CTScott]

Thank you so for your reply Scott! I shall do just that!
But I just want to double check.
Will I then have a problem with the ECM and A/C ECU not receiving that signal or will it not really effect anything worth worrying about?

That is a good question. The service manual does not explain if lacking that signal will cause an issue. I would say to connect it up and then try the A/C. I suspect that it will still work fine. It is probably more of an issue for "cold weather package" Yaris, which have the PTC heater. That may be what the AC ECU prevents from powering, unless it sees the alternator output signal.

[Yaris Lighter]

That is a good question. The service manual does not explain if lacking that signal will cause an issue. I would say to connect it up and then try the A/C. I suspect that it will still work fine. It is probably more of an issue for "cold weather package" Yaris, which have the PTC heater. That may be what the AC ECU prevents from powering, unless it sees the alternator output signal.

Ok Scott I need your brain again!! After a closer look at the wires on the HOA, I found a 4th pin that didn't have a wire to it. Seems like they just wanted to use three wires. So I was able to rig it to where I then had 4 wires. But now... the "fun" begins.
After days of working on cutting pieces of the HOA, finding new bolts, extending wires and all that jazz I was eventually able get the HOA on and in the right place so the belt wasn't slipping off and able to spin all the wheels correctly. I hooked up all the wiring and everything seemed great but my Idiot Light was on when I started the car. I wasn't too worried at first because I have a digital gauge + terminal and the voltage was reading at 14-14.5 for a good 5-7 minutes so I just figured oh well and happy day. However, after starting the car up a second time the voltage on the gauge wouldn't go pass 12.1. It would fluctuate at 11.8-12. I turned the car off and on again with the same results. I hadn't touched anything from when the gauge first read 14+. So I pulled out my multimeter and thought maybe a connection came loose on my Voltage Regulator wiring but this is the readings I found:
S wire 11.8 v
I wire 11.8 v
L wire is only at .9 v (causing the idiot light I bet)
Lastly the M wire (the one I rigged) is at 5 v

Do I need to switch or combine some of the wires? I have them all in the right places I thought. I followed what we had discussed before so IDK what to do or what changed from the first time I turned the car on after hooking up the wiring. I’m going to unhook the M wire I assembled to see if that changes anything. Maybe the pin was unused for a reason=D. Please let me know what you think and thanks for all your help Scott!

[CTScott]

Ok Scott I need your brain again!! After a closer look at the wires on the HOA, I found a 4th pin that didn't have a wire to it. Seems like they just wanted to use three wires. So I was able to rig it to where I then had 4 wires. But now... the "fun" begins.
After days of working on cutting pieces of the HOA, finding new bolts, extending wires and all that jazz I was eventually able get the HOA on and in the right place so the belt wasn't slipping off and able to spin all the wheels correctly. I hooked up all the wiring and everything seemed great but my Idiot Light was on when I started the car. I wasn't too worried at first because I have a digital gauge + terminal and the voltage was reading at 14-14.5 for a good 5-7 minutes so I just figured oh well and happy day. However, after starting the car up a second time the voltage on the gauge wouldn't go pass 12.1. It would fluctuate at 11.8-12. I turned the car off and on again with the same results. I hadn't touched anything from when the gauge first read 14+. So I pulled out my multimeter and thought maybe a connection came loose on my Voltage Regulator wiring but this is the readings I found:
S wire 11.8 v
I wire 11.8 v
L wire is only at .9 v (causing the idiot light I bet)
Lastly the M wire (the one I rigged) is at 5 v

Do I need to switch or combine some of the wires? I have them all in the right places I thought. I followed what we had discussed before so IDK what to do or what changed from the first time I turned the car on after hooking up the wiring. I’m going to unhook the M wire I assembled to see if that changes anything. Maybe the pin was unused for a reason=D. Please let me know what you think and thanks for all your help Scott!


My bet is that the alternator is generic, so I would not hook up the extra wire to the M terminal unless the alternator manufacturer can confirm its purpose.

I would also not move or combine wires. They are labeled, so verifying that the labeling is correct should be done with the manufacturer as well.

The low voltage on the L wire does explain the idiot light not working. The low voltage on the second run almost makes it sound like something already failed within the alternator, since you are reading battery voltage, rather than a higher output voltage from the alternator. Check the two large fuses on the positive battery terminal red plastic chunk to make sure one of them did not pop.

[Yaris Lighter]

My bet is that the alternator is generic, so I would not hook up the extra wire to the M terminal unless the alternator manufacturer can confirm its purpose.

I would also not move or combine wires. They are labeled, so verifying that the labeling is correct should be done with the manufacturer as well.

The low voltage on the L wire does explain the idiot light not working. The low voltage on the second run almost makes it sound like something already failed within the alternator, since you are reading battery voltage, rather than a higher output voltage from the alternator. Check the two large fuses on the positive battery terminal red plastic chunk to make sure one of them did not pop.

Alright! I got in contact with the company and they conformed all the wiring is labeled correctly. I pulled the wire I rigged and also unhooked all my wiring I had connected to start from scratch. I turned the car on and took a multimeter to all the wiring and found these results coming from the 4 wires from the car.

The Green wire 12v, White 12v, Pink 12v and the Blue was only at 8v. when the car was off all the wires became cold except the white wire which then read 11 something v coming from the battery. So I know the white wire is correct and has to be the "S" wire for the Voltage Regulator. Because, the "S" wire is suppose to monitor the battery (right?). So I thought to myself well.. seeing as how I only have two wires left to worry about (The "L" and "Ign." wire) I figured I'll just plug the last two wires reading the 12v into those two. Since the green wire from the 4 pin wires was suppose to go to the Ign. wire on the VR I kept it that way and then hooked the Pink wire to the "L" wire. I know on the diagram above it shows it going to the A/c Ecu but I figured wth lets try it and all in all it's working for some odd reason? My battery light is no longer lit and my battery is charging. I took my car for a spin turning on every electronic I could and the charge wouldn't drop below 13.7 v and can still use all electronics without incident So...

Working for me!!:bow:
HOA's Blue "S" wire to Plug's white wire
HOA's Green "Ing" wire to Plug's Green wire
HOA's Yellow "L" wire to Plug's Pink wire
Plug's Blue wire capped

Thank you for your time and help Scott! Couldn't have gotten this far without your input. :thumbup:

[sebastblast]

I know it's a very old tread but i have the same problems with my 2006 yaris. i want to replace my 320k yaris with a 125k echo but the echo have only 3 wire. somebody try this swap before?

thank you.

[CTScott]

I know it's a very old tread but i have the same problems with my 2006 yaris. i want to replace my 320k yaris with a 125k echo but the echo have only 3 wire. somebody try this swap before?

thank you.

I would stick with a Yaris one. You can pick up used ones pretty inexpensively. With the Echo one the charge light will always be on.

[sebastblast]

thank you for the information, i will do it this week-end.
sebast.