V3.3 was populated with D100, a protecting 18V zener (between injector flyback rail and GND5) that provides some protection (for the 8 injector-FETs) if the user forgets flyback connection (but doesn't use injector PWMing).
However, when PWM-ing is applied (non 100% duty) and powerflyback is used, if injector-common+ is above appr 13.3V
- the 18V zener (with very low Ampere rating) will clamp to GND5
- not towards injector-common+ through the 5*diode drop powerflyback (which is desired, since the powerflyback has high, >20A peak current rating).
Unfortunately the powerflyback was tested with 12V supply and D100 sneaked attention.
Note: assembled controllers sent out after 2006-jan-11 have these removed.
D100 diode to remove marked with yellow
D100 is also different from the rest, different shade and text is PJ52LM (not ES2J).
Customers who ordered assembled controller with powerflyback option and don't want to remove D100 themselves should ask in webshop and we provide address a shop on their continent to do so.