ABS Wave Forms

[David Green]

Hi Dave , how long does the vp record for ? , have only tried it for about 10 mins .I'm pretty confident it will pick up clitches ok .As for you scope trace , try again to send the scope movie .I haven't had any bother with that .I just save the file ,pop it on shop stream then name it to what i want and have a nice look

Have some nice scope movies at work to look at

Regards
John

Hi John

Thanks for the additional info, I read the 2009 VP online manual yesterday, apparently if you setup the VP to capture glitches it will do it no problem, however nowhere on the VP does it educate to advise how to set it up to use it correctly?

Now some of this could still be user error, but for me it just goes to show that nothing beats a manual which can be read to understand how to use a product correctly.

David

[greasybob]

Here is another two wire ABS comparison, you can see the left side signal dropping out at low speeds creating the phantom ABS activation. You can see in the scope shots the difference in amplitude between left and right even at similar speeds, suprised the left side registered at all. The vehicle is a 2000 Expidition. A new speed sensor fixed the problem.

[hefaus]

WSS Waveforms

Hi greasybob. Thanks again for the waveforms

[David Green]

My ABS signals don't look like greasybobs, but at initial low speed my graphs start off like the first one then as speed increases look like they do in my example, so if the VP can display graphs like greasybobs examples, can someone please advise what the VP scope setting should be?

My settings chosen were copied from an example scope setting on this forum, although my scope displays are not as good as the examples I took the voltages and ms displays from?

David

[greasybob]

I got my scope recording by back probing the sensor and spinnig the wheel by hand when the vehicle was on the hoist. I used a 1 volt scale and a 1 second sweep. I understand your problem of not having scan data at higher speeds, most american cars will show speed on the data list at highway speeds.