no tach/rpm signal to MS with edis

jakeb · Post by **jakeb** » Tue Jul 25, 2006 8:57 am

I am hooking up my edis but I am not getting a tach signal to the MS. I am getting power to the edis module and I am getting 5v on pin 3(saw)

The car is running on a carb and distributer right now but I am not getting any signal to megatune.

Is there a way I can test the VR sensor? Or the edis module?

Also I do not have the coil connected right now as I am testing things. Will that make a difference?

The VR sensor is less than 1mm away from the crank wheel. One thing that I worry about is the sensor is not perfectly centered on the wheel. I had to move it a little bit to get it out of the way of the belt but it is almost centered.

any help would be appricated.

TIA,
Jake

superchargingmachine · Tue Jul 25, 2006 9:16 am

The sensor can be tested by connecting the leads to a multi-meter and moving a piece of metal in front of it. It should give a quick negative or positive.

I am not positive but I would think the module would work if it has power and ground whether it is connected to the coils or not.

I run my VR about 0.5mm from the wheel. I'm not sure how far away it can be before the signal will be too weak.

You might try reversing the wires to the VR. Also are you using shielded wire for the VR leads going back to the EDIS.

jakeb · Post by **jakeb** » Tue Jul 25, 2006 9:40 am

Alright I took the sensor off..connected to a multimeter and waved a metal wrench in front of it and I did get a small reading on the meter. under 1v, more when the wrench got pulled in my the magnet.

I tired having the wrench a bit off center from the sensor and I got the same result.

Yes I am using shielded wire going from the VR sensor to the edis module.

any other ideas?

TIA,
Jake

Post by **jsmcortina** » Tue Jul 25, 2006 9:48 am

Swap the VR sensor wires. This is the most common cause for no rpm.

James

jakeb · Post by **jakeb** » Tue Jul 25, 2006 10:04 am

After I thought I checked and read and checked again I had the wires backwards. I had them wired the right way once and change them because I found a diagram that showed otherwise.

I just used some jumper leads and flip flopped the wires and now I am getting a tach siginal...

What a great project and group of people.

thanks a lot all!!!

Jake