Reading Codes
 

Question: Can you pull fault codes on a 1993 300E with the 2.8 104 engine. I have the 16 pin connector but it does not have the built in LED. I made the homemade code reader but all that I get when I activate the button is a solid red light from the led, no flashes. Before I kept trying I what to make sure that you can read the codes on this model. Thanks,

Bill

Yes you can read codes on the 300e 2.8
you should use the homemade tool as follows:

connect the black wire to pin 1 (ground)
connect the red wire to pin 16 (+12 V)
connect the 3rd lead to any of the other diganostic pins (3, 6, 8, 14...)
--It appears that you've done this correctly since the LED is on

To read codes: (With the ignition ON but engine off - all the gauge lights will be on)
1. press and hold the switch for 2 - 3 seconds
2. release switch and count the number of blinks of the LED
--this number is the code
3. repeat until you get the first code again (it cycles through in numerical order)

To reset codes:
1. read the code as above
2. hold the switch down for 8 - 10 seconds

each code must be read and cleared individually