SS Relay to replace RED FP relay

[wazzz]

No diode is needed for the FP relay on a CIS, as there is no electronic driver circuit to protect upstream.
Subject is about modifying a F9 SSR to drive a FP on a CIS car, which I think is not possible.

[AndrewCologne]

No diode is needed for the FP relay on a CIS, as there is no electronic driver circuit to protect upstream.

Yes it is needed on newer sc with RPM limiting switch and btw. it is exactly the difference between a black and a red relay.

Watch the wiring diagram as on the red FP relay terminal 85 and 86 the RPM limiter switch is directly connected. And as this RPM limiting unit holds sensible electronics you should at least make shure that a flyback diode is present in a relay like used in the red one. Once the Relay switches off the inductive load of the relays coil will give a voltage spike towards the RPM limiter.

Originally Posted by wazzz

Subject is about modifying a F9 SSR to drive a FP on a CIS car, which I think is not possible.

And here I'm with you.