2003 Yaris High Alternator Voltage

[drcurzon]

Hi There,
I have a 2003 Toyota Yaris.
The battery warning light is on on the dashboard, and the alternator is producing around 17v. I've had the alternator checked, and it seems to be okay.
The only things I can think of are that either:
- The regulator has failed in the alternator
- The car isn't telling the alternator to stop increasing voltage

There is a blue wire connecting to the alternator that I believe goes to the engine management connector, could it be that the wire between the alternator and ECU has broken?

Many thanks in advance, Daniel.

[ecc_33]

Mine did the same thing and the alternator regulator was bad. install a new alternator and your good to go.

[Geoff Peace]

Hi There,
I have a 2003 Toyota Yaris.
The battery warning light is on on the dashboard, and the alternator is producing around 17v. I've had the alternator checked, and it seems to be okay.
The only things I can think of are that either:
- The regulator has failed in the alternator
- The car isn't telling the alternator to stop increasing voltage

There is a blue wire connecting to the alternator that I believe goes to the engine management connector, could it be that the wire between the alternator and ECU has broken?

Many thanks in advance, Daniel.

An alternator voltage of 17v is most certainly not OK. 13.6 to 14.4 volts is the regulated output. !7v could cause damage to other components. Needs to be checked by an electrician to establish the cause.

Regards Geoff Peace.

[BLH]

I would get it checked as soon as possible.
When I was fixing Motorola Two Way Radios. I had a similar situation. The voltage almost fried the low voltage high power transistors in the radio transmitter. It also was actually boiling the battery electrolyte.