Car Alternator

The alternator has four wires labelled S, L, IG and B.

S is the "Sense" wire that tells the regulator battery voltage, so that
it can adjust the charging rate. Flat battery - high rate, full battery = low rate.

L is for the charge indicator light. When the alternator is charging, the
voltage on this wire cancels the charge warning light.

IG is a switched supply from the battery to provide the initial kick (excitation)
to make sure that the alternator starts generating when the engine starts.

B is the battery wire. This is the heavy wire that connects the alternator to
the battery, and carries the full charging current
Click to expand...
.

I think someone tampered with the wiring for whatever reason and that is why you are having issues now.
 
Here's a picture of the Bosch terminals:
https://ibb.co/gtyugc

It doesn't have three terminals.
Maybe the mechanic didn't connect the new one correctly.
Where are the other two wires for connection, I don't see anything under the hood.
 
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Trust|Nobody said:
Here's a picture of the Bosch terminals:
https://ibb.co/gtyugc

It doesn't have three terminals.
Maybe the mechanic didn't connect the new one correctly.
Where are the other wires for connection?
Click to expand...
IG is a switched supply from the battery to provide the initial kick (excitation)
to make sure that the alternator starts generating when the engine starts.
Click to expand...

I strongly suspect this ^^ is what you are missing from you alternator and I strongly suspect that white cable has something to do with it. There's a colleague who has a Tazz, seeing that the engines look similar, I will ask if I can take a look and see how the wiring goes. I don't know if he'll agree as some people are so touchy about their cars but I will ask nicely.

Maybe on your older Bosch the excitation part happened automatically while on this one it must be triggered?
 
Trust|Nobody said:
The location of the white cable is circled in red (between the two pipes). And the location of the alternator is circled in green.
https://ibb.co/hoYAMc

The mechanic said it might be a cable to a temperature sensor.
Click to expand...

I just checked and it looks like it has nothing to do with the alternator, looking down on your engine where the engine is connected to the gearbox on the engine side you will see a greyish plug, that is where the third cable goes on his car and I suspect on yours too. Coming to the alternator, he still has the Bosch that is the same as yours, no three pin connection.
 
Trust|Nobody said:
I think it may be that the new alternator is not connected correctly! We only have one of the three connections connected.

There supposed to be a plug connection like this:
http://wilbo666.pbworks.com/f/1303822408/201104262158_Toyota_Alt_Pinouts.png

From:
http://wilbo666.pbworks.com/w/page/39441708/Toyota Alternators
Click to expand...

I think I know what is happening now, your old alternator has inbuilt 3 pin connection, while you new one is not inbuilt and you should wire them.
 
Trust|Nobody said:
I think it may be that the new alternator is not connected correctly! We only have one of the three connections connected.

There supposed to be a plug connection like this:
http://wilbo666.pbworks.com/f/1303822408/201104262158_Toyota_Alt_Pinouts.png

From:
http://wilbo666.pbworks.com/w/page/39441708/Toyota Alternators
Click to expand...

I think I know what is happening now, your old alternator has inbuilt 3 pin connection, while you new one is not inbuilt and you should wire them.
 
S - This pin is used to sense the voltage at the battery, This pin is connected to the positive terminal of the battery at all times, in most wiring arrangements via a 7.5A fuse marked ALT-S (Alternator Sense).

L - This pin is used to turn the alternator charge warning light ON / OFF, This pin is Grounded by the regulator as required to turn the alternator charge warning light ON. The alternator charge warning light should be wired with one side of the light connected to battery voltage (Ignition Switched) and one side of the light connected to this regulator pin. Light ON = Error Condition, light OFF = Normal.

IG - The alternator regulator is turned on by this signal, This pin is connected to battery voltage when the ignition switch is in RUN and CRANK positions.

As I said before your alternator regulator is not getting a signal to turn on, hence you aren't getting any voltage from the alternator.
 
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