I have tested by piercing the signal wire with the engine off so you do not short anything. Get past the outer shielding and into the center wire, if you have one of those little Hook type ends for you red lead of your VOM they work great. Then ground the black lead to your seat bolt and set meter to DC Voltage. Then start the car and it should be not moving and a steady .45 ish readinng until it fully warms up and the CIS-E system goes to closed loop operation. Then you will notice the voltage swinging properly, if the engine is cold you will most likely get a rich reading, over .45V. If you are talented enough go for a drive will glancing at the VOM once in a while. Once at speed you will notice it go up and down around the .45 reading. When accelerating it will go lean briefly and then to rich. When at WOT it should be above .8V until you let off the gas. This would indicate that your EHA and AFM are working properly. I actually set my EHA and IACV using the O2 reading. Got them back to where they should be after I screwed with them stupidly chasing down a rough idle and poor fuel economy. That was when I first started with the 190 before I realized there were other things wrong. Good luck.

__________________
~Jamie
_________________
2003 Pewter C230K SC C1, C4, C5, C7, heated seats, CD Changer, and 6 Speed. ContiExtremes on the C7's.

1986 190E 2.3 Black, Auto, Mods to come soon.....