Flyback?

[GintsK]

Ground side is disconnected.
So one side of injector is connected to injector common (not connected to any where when relay is off) other side to battery. If injector at that time becomes unpowered (we switch off supply during injection pulse) between both sides of injector rises sharp voltage spike. But our Zener/TVS diode do not work anymore because open circuit. So we have risk that injector common gets -200V. And this voltage then goes to another electronics trough injectors, IACV, solenoids.

For ilustration:

Am I wrong?

Gints

[rob@vems.co.uk]

Now, I have doubts... Have I been reading the schematics wrong all this time: http://www.vems.hu/files/genboardv3/v3.6/genboardv3.6_sch.pdf ?

[GintsK]

Schematic is correct except D100. We have no D100. "flayback pad" is where our TVS is connected with other side to injector common.
In my  last picture fused line assumes our discussed flyback connection to +Batt.