Author Topic: IAC flyback and wiring  (Read 6195 times)

Offline lugnuts

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IAC flyback and wiring
« on: July 28, 2008, 05:53:43 am »
I'm using a Bosch 2 wire PWM style IAC motor on my builds. I have had this valve operating well on the workbench using the Inj ch7 output (with the engine off - no other injectors being used)

I am using a IN4007 diode across the + and - at the valve connector, this gives me twice the duty cycle resolution making the valve very useable.

ECU flyback is: "30v Flyback"

My question is, what if any wiring modifications are needed to protect the ECU?

In the following 2 scenarios, what modifications, if any, are needed?
1) IAC powered by key switched 12v.
2) IAC powered by Injector 12v. 

thanks,
Kevin
 

Offline rob@vems.co.uk

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Re: IAC flyback and wiring
« Reply #1 on: July 28, 2008, 04:13:47 pm »
1) None
2) As long as the feed is not interrupted by the flyback diode (the feed is before the injectors flyback rather than after it) then none.

Rob

Offline lost

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Re: IAC flyback and wiring
« Reply #2 on: April 03, 2010, 02:49:01 am »
Same configuration. idle valve with 4007 diode on injector chanel 7, and boost valve on ch 6.

Power for idle valve: Key switched 12v(relay)  ---to  fuse  -- to  Idle valve with diode across it

Power for boost valve: Key switched 12v(relay)  ---to fuse  --  to boost valve

Other wire goes directly to vems inj. pin.

So they are injector chanels, and flyback is not connected to vems. it goes straight to fuse that is switched on with master relay that turns vems ON.