VEMS Community Forum

Technical => Wiring & Sensors => Topic started by: boostd audi on April 30, 2014, 03:14:24 PM

Title: wiring wheels speed to pin8, from an abs ring
Post by: boostd audi on April 30, 2014, 03:14:24 PM
i have a vw and I thought I did this before, but my car had the ps2 wire.  now my new ecu has wheelspeed on pin8 built in.

I want to get the wheelspeed input from a non power driven wheel using it abs sensor ring.


I bought the vr/hall adapter for wheelspeed .
i am assuming i solder my abs sensor to the adapter converter
then plug it into a db9 that has ground, +5, and wheelspeed signal (pin8). from ecu.

i hope this is right.  thanks for the help in advance

i wired like this and i have not gotten any signal out of the abs ring.  what am i doing wrong??

(http://i92.photobucket.com/albums/l40/bdcoombs16vt/vemswheelspeedwiring_zpsb5f63bb3.png)
Title: Re: wiring wheels speed to pin8, from an abs ring
Post by: boostd audi on April 30, 2014, 05:06:12 PM
what divider did you have the solder blob in the converter, using a vag abs ring?

i believe the abs ring from this vw has ~45 teeth so i am guessing i need the divby4 not by 8
Title: Re: wiring wheels speed to pin8, from an abs ring
Post by: boostd audi on May 01, 2014, 03:27:51 PM
man this forum has died.

I think I have it wired right. im going to try changing divider this weekend and hopefully I can get it working.
Title: Re: wiring wheels speed to pin8, from an abs ring
Post by: mattias on May 02, 2014, 12:21:05 AM
Oscilloscope.
Title: Re: wiring wheels speed to pin8, from an abs ring
Post by: VEMS on May 05, 2014, 06:10:47 PM
Hello Boostd Audi,

In verifying the chain from ABS ring to ecu, its best to split in a few separate easy checks:

1) Measure VR sensor resistance, without  VR/Hall converter connected with DVM (Digital Volt Meter) in resistance mode (0-2kohm)
2) With DVM measure in AC voltage mode (0-2v), the voltage across VR+ and VR- of abs sensor without the VR/Hall converter connected to it, while turning the wheel as fast as possible by hand
3) Verify if the correct divider setting jumper is soldered
4) Verify wiring/connection to VR/Hall convertor (pin#1: 5v, pin#4: signal out, pin#5: GND)
5) When turning the wheel by hand verify (if possible by scope but DVM (in DC voltage 0-20v) should do at these low speeds), if you see alternating high and low voltage state.

If you can get back to me with readings/measurements and observations from tests above i can help you diagnose why it is not operating as intended.

Best regards,


Dave

Title: Re: wiring wheels speed to pin8, from an abs ring
Post by: boostd audi on May 18, 2014, 06:22:43 PM
thanks guys.

I didn't have the scope with me when I wired it.  I am going to see my buddy this week to test it and hopefully get it dialed in.