Sharing VRS signal

4600cc · Post by **4600cc** » Thu Jun 08, 2006 2:59 pm

Suppose you have an ECU that uses VRS and 36-1 tooth gear, and you want to install EDIS + Megajolt and still use that same VRS sensor. How would one go about this? Is there a circuit that could be made to share this single VRS. I know that connecting VRS to ECM and EDIS in parallel won't work, since both ECM and EDIS send a refernece voltage to VRS.

I'm thinking of a circuit that would read VRS and have inputs for ECU and EDIS and madulate those inputs accordingly. Electronics is not my thing though, please somebody think of a simple solution. Just image you want to run two EDIS modules off a single VRS sensor.

AL

MartinM · Post by **MartinM** » Thu Jun 08, 2006 3:54 pm

...I know that connecting VRS to ECM and EDIS in parallel won't work, since both ECM and EDIS send a refernece voltage to VRS...

I'm pretty sure that there's no voltage sent to a VRS - the VRS is just a magnet with a coil that responds to passing ferrous material and produces a sine wave ac voltage, magnitude depending on speed of the passing ferrous material - IIRC from a few tens of mVolts to a few tens of Volts

So I reckon you *could* supply two systems with the output of one VRS.

YMMV...

4600cc · Post by **4600cc** » Thu Jun 08, 2006 4:43 pm

Yes you right. A quick reference to Ford Fuel Injection & Electronic Engine Control proved that. So you think hooking EDIS and ECM in parallel to this sensor will not effect anything? Sounds sweet!!!!

MartinM · Post by **MartinM** » Thu Jun 08, 2006 5:55 pm

Gotta be worth a try....

Post by **brentp** » Fri Jun 09, 2006 3:48 am

If the impedance on the VRS inputs is high enough, it will be able to drive both.

Failing that, another option would be to use an op-amp or simple transistor amplifier.

Brent