Trailer ABS testing.

Yep. I have a spare plug with wires sticking out. Use white wire on the top hole, then test abs with the blue en red wire in the hole directly on the right.

For diagnostic plug in blue wire for 1 second and take it out and then put it right back in.

 

One at a time. If the abs light stays on with power on the blue wire its a cut/open wire somewere on trailer. If it stays on with power to the red run diagnostic.

To get a code plug the blue wire for 1 sec, take it out and put it right back in. Light will pop 1 time and close. After that it will start blinking giving you the code.

 

I'm about to test this Monday when I get home. So what exactly do you mean by hot wire?
My guess is a wire from the -black conector of the batteries. Right the rest I have it all line up.

 

Nailed it. Gave me 4 blinks on a wanbco. Checked the omhs and voltage of the sensor measures where good for the 2 sensors,so checked continuity for the cable going to the abs unit, and boom was the cable didn't have continuity. Got a new cable and abs is good again.

Thanks for letting me know how to get the codes!

Very helpful also:

http://www.meritorwabco.com/MeritorWABCO_document/mm33.pdf