I have a te31 corolla with a 2tc. I had an issue sourcing the right alternator. My model is odd, it has a 5-wire alternator when all of the others that I find have 6-wire alternators. Looking it up by my model year only gives me the 6-wire alternator as an option. In order to find the right one, I had to look it up under Toyota pickup of the same year. The wiring harness on my car doesn't look modified as well so it doesn't seem like a franken job from the previous owner.

I was wondering if I changed the pigtail on the harness and installed the 6-wire alternator, will it cause any issues. It has more amps than the old one so it would be a little nice to use it.

Do the contact labels bear any resemblance to these? Are the wire colours similar? Does it have an external regulator?

I can't imagine why they need so many wires to an alty, three or four will do it.

Both have external regulators. I've been having trouble figuring out what the 6th wire is for. According to these diagrams it seems like it might just be a grounding wire, but I wouldn't want to be wrong. Main difference is the pigtail itself but even then, the pigtail on both only has 3 wires in it. 

Edited September 11, 20242 yr by Bobbyfanatic

Not sure why it uploaded both of the same pictures, but here is the 2nd diagram.

On 9/7/2024 at 4:36 AM, altezzaclub said:

Do the contact labels bear any resemblance to these? Are the wire colours similar? Does it have an external regulator?

I can't imagine why they need so many wires to an alty, three or four will do it.

I might just try to suck it up and convert to a totally new alternator with internal regulator.

They look like typical 4-wires altys, the layout is the same, F N B E.

So F is WG or R

N is L or WL

B is W on all

E is WB on all.

Anything else is not needed in theory.

What do you mean when you say a 'pigtail'?  Are you referring to the power-out terminal B with the white wire that powers the whole circuit?  ..and motors like mine have another 6 wires piled on top of it!

 

On 9/11/2024 at 1:50 AM, altezzaclub said:

They look like typical 4-wires altys, the layout is the same, F N B E.

So F is WG or R

N is L or WL

B is W on all

E is WB on all.

Anything else is not needed in theory.

What do you mean when you say a 'pigtail'?  Are you referring to the power-out terminal B with the white wire that powers the whole circuit?  ..and motors like mine have another 6 wires piled on top of it!

 

I'm used to calling connectors "pigtails". The multiwire plastic connectors. 

'I'm used to calling connectors "pigtails". The multiwire plastic connectors.'

Fair enough, I've seen any short bit of wire called a pigtail here and there. I did a search for a 6-wire alty and got a 6-phase, which I'd never heard of...

"A standard alternator is generally 3 phase. This means that there are three “legs” of the stator that fire in succession as the alternator spins, A-B-C-A-B-C-A-B-C producing alternating current.

6 phase alternators have two 3 phase stators inside the alternator that are slightly out of phase of one another. The two stators fire in succession like this: A-a-B-b-C-c (the second stator is in lower case) Because they are slightly out of phase with one another, there is a cancellation of electromagnetic harmonics that makes the alternator run more smoothly and more efficiently. This allows for cooler operation, more output from a smaller overall housing, and MUCH better durability.

The rectifiers turns the AC current coming out of the stator into DC current. DC current is what is used in an automobile. By passing trough the diodes, half of the AC current is burned off in the form of heat as it is “rectified” into DC current. That heat is what eventually kills alternators. By having (2) rectifier plates, there is much more surface area to dissipate the heat. This is especially important in a high output alternator- as the more amperage the alternator makes, the more heat is generated. Also, by having (12) or (16) diodes (depending on which 6 phase alternator you are talking about) the heat and electrical load can be distributed more evenly throughout the rear of the alternator housing."

That's from guys who put 160db sound systems in their 'trucks'.

The other 6-wire answers were the little 6-pole altys in scooters that have 6 windings at 90deg to a usual alty.