The 94-95 E320 (124 body) has on-board diagnostics to monitor the emissions system. If the light has come on a code has been set and it DOESN'T need a scanner to be retrieved. Even if the light is now out the evidence of that code will remain for something like 40 or 80 drive cycles.
The code can be retrieved on these two years of 124 chassis (and some Ca models of other chassis) without scan tools. The impulse light is built into the diagnostic connector. There is a button next to the red led. Turn key on, engine off, and push the button and hold for 2-3 seconds. Release and the led will blink a code. One blink is "no faults". If a code is read, do the process again to read a second code. Keep reading codes till the first code re-appears.
The diagnostic connector is in the well in front of the battery, mounted high on the bulkhead separating the area from the motor. It has a two width rectangular cover with a small straight ridge for gripping and removal. Underneath are 16 round ports and the button and led. The cover may be missing.
Owner 24 bay BSC
Bosch Master, ASE master L1
26 years MB technician
[This message has been edited by stevebfl (edited 06-25-2000).]