The 'E' Type Forum

Aloha!

Most 4TR controllers are with 3 pins, others with 4. For what is the fourth for? I enclose pics of two units, the most left connector is marked with B+, the other has A. Are they the same still? Both are NOS-parts.

Oops, I was able to add any pics as a new member or I don't know how to do it.

This will help you how to post photos then we can better understand your question:
viewtopic.php?f=2&t=19527

And welcome to the best place for all things E Type

Geoff

From Rimmerbros website;

https://rimmerbros.com/Item--i-BHA4789