MoTeC Global Forum

Hello
Is it possible to run my OEM Honda NSX ABS 2 wire sensor for wheel speed on Digital inputs?

Would I need an analogue to digital converter?

Thanks in anticipation

Did you ever figure this out?

Hi,

I know that the original post is from a while ago and wasn't answered at the time (unsure why), but I'll answer it now for both of you.

The wheel speed sensor will be either a Mag sensor or a VR sensor, both of which can be read by a Digital input (the sensor looks for the 0V crossing in the sine wave as it's trigger point) and used for a speed input into the ECU. The Mag sensor has one pin (either can be used, this swaps the direction of the wave) that is connected to one of the ECU 0V pins, and the other to the Digital input. The sensor itself generates the voltage signal that is read by the ECU.

VR sensors (Used on Mitsubishi EVO's amongst others) are wired differently as they also need to have BattV+ supplied to one pin (normally marked) and the other pin spliced into two outputs, the first connected to the ECU through a Digital input and the second to the ECU 0V pin through a 220ohm (typical) resistor.

Thank you sdean. I didn't want to recreate another post covering same subject, which is why I commented on his post.

yes nsx speed sensors are mag. In nsx shop manuals doesn't say anything about requiring 12+v. Just to double check the mag sensors doesn't require use of resistors. Only the VR style that's uses 12+v feed uses the 220ohm resistor. Correct? Thank you so much

The description of adding 12V and extra resistor sounds like the conversion of 2-wire current-loop Hall Effect sensors (as used on Nissan 350Z/370Z). The curernt lops sensors uses either 4mA or 20mA depending on whether the trigger is sensed. You need to provide a voltage divider that can present this change so it can be detected by the digital inputs.

If the NSX sensor are pure VR / Magnetic then the voltage supply and current dividing/limiting resistors aren't required.