Alternator question

[chrisbee1961]

First posting to forum so hope I have chosen the correct section.

The alternator on my 2004 WRX recently failed.  This is a Mitsubishi A2TB5391 / OE 2700AA420.  The fault code P0558 - Generator Circuit Low Input is flagged in the ECU. 

In the alternator plug, there is the blue wire on pin 3 for the "C" signal for smart charging,  According to the Subaru FSM, this smart charging is only on the STi, which mine is not.   Does Subaru fit a standard loom with this prewired but doesnt connect it to the ECU, or would it be active on my vehicle ?

I believe the OE alternator has smart charging capability.

Thanks in advance !

 

[Tidgy]

assuming its what im thinking of the smart charging thing is a pita, its known to fail, did on mine. There is a bypass mod that can be done (what mine had), not sure what it entails though im afraid as clinic did it for me.

[chrisbee1961]

Thank you for your reply Tidgy.  The original alternator had failed due to corrosion of the electrical strapping between the rectifier and the voltage regulator.  I guess not bad after 21 years.

I did replace it with an AS-PL A5194 alternator that did not have this smart charge feature and the P0558 came back, although it was charging.  This was showed on the AutoDoc website to be compatible, but wasn't.  I have since ordered the AS-PL A5074 which is shown to be compatible by the manufacturer.

I am aware of the modification and is detailed here https://www.strongforsubaru.com/subaru-alternator-fault-fix/

[Tidgy]

9 hours ago, chrisbee1961 said:

Thank you for your reply Tidgy.  The original alternator had failed due to corrosion of the electrical strapping between the rectifier and the voltage regulator.  I guess not bad after 21 years.

I did replace it with an AS-PL A5194 alternator that did not have this smart charge feature and the P0558 came back, although it was charging.  This was showed on the AutoDoc website to be compatible, but wasn't.  I have since ordered the AS-PL A5074 which is shown to be compatible by the manufacturer.

I am aware of the modification and is detailed here https://www.strongforsubaru.com/subaru-alternator-fault-fix/

I'm not sure tbh, i'll ask clinic tomorrow, or later today haha