1991 190e 2.3 0% duty cycle

[LJetronic]

Hey guys, i really need some info here! I recently purchased a 91 190e, and am not too familiar with the engine management system. The car idled high when purchased, and after some diagnostics, found the throttle position sensor to be bad, i replaced it and now it idles well. I attempted today to check the duty cycle at the X11 port between pins 2 and 3. Engine off, the duty cycle was calculated to be 85% which according to landiss indicates a california controller. After startup and at operating temp, the duty cycle seems to be 0%, that is, pin 3 has battery voltage and does not fluctuate. I attempted to adjust the CO at the afm, but this had no affect on the duty cycle but DID affect running. I checked to see if the O2 sensor was making a signal, and it is, oscillating around .2 volts. Whats the deal? Is the computer bad? or is the EHA not responding to the computer? Can anybody turn me on to some shop manual reading on this subject? thanks!!