Subaru Alternator and ECU Reset

for questions and answers about alternative power transplants on the T25, GTi, Porsche,Subaru etc, this is the place. You must register to post but anyone can read.

Moderators: User administrators, Moderators

Post Reply
mshaw1980
Registered user
Posts: 588
Joined: 10 Aug 2015, 06:50
80-90 Mem No: 14800
Location: Peel, Isle of Man

Subaru Alternator and ECU Reset

Post by mshaw1980 »

Hello

Has anybody seen something to do with resetting the Subaru ecu if it is not putting out 13.5 to 14v? I tested mine yesterday after I noticed the voltage sensitive relay I fitted wasn't working. Turns out the alternator is only putting out 12v so obviously the split charger is not working. Also my dash is not currently working and so no alternator light. I read somewhere as well the alternator light on a Subaru has to be working in order for the ecu to allow full output voltage of the alternator to be given out
1987 VW T25: Subaru EJ20 using RJES parts (If it was meant to go fast it wouldn't be brick shaped!)

User avatar
syncroandy
Trader
Posts: 1857
Joined: 18 Oct 2005, 18:15
80-90 Mem No: 851
Location: North Lancs. UK
Contact:

Re: Subaru Alternator and ECU Reset

Post by syncroandy »

Just checking, you did fit voltage-sensitive relay to the main alternator output, *not* the regulator D+ ?

IME the common VW camper trick of using the alternator D+ output power a split-charge relay doesn't work, as the Subaru regulator doesn't provide enough current to trigger a normal relay coil. It possible that leaving such a relay connected might interfere with the regulator function (I can't swear this this mind). Sounds to me like the same issue.
Syncrosport
Volkswagen Transporter, reloaded.

252 GC5 EJ25 AAN L90D
246 097 AFN AVL+ L90D
Syncronaut #004

Post Reply