Clearing Check Engine Light, '94 E320

[Ron Johnstone]

My '94 E320 Wagon displayed the Check Engine Light. I used the code checker that I built to display the codes and to see if the warning was real, I erased them and finally used the built in "button" on the 16 pin DTC to turn off the Check Engine Light, which it did.
About a day later, the Check Engine Light came back on, but when I did a code check, I only got one flash on both pins, which means that no codes were stored.
Any ideas as to what is causing the light to come back on and how do I finally turn it off would be greatly appreciated.

[mbdoc]

Most likely issue is the oxygen sensor..

HOW many blinks did you get the first time?

[Ron Johnstone]

Using the "Arthur Dalton code reader", I get only one blink on pins 8 and 14, but when I use the button and led on the 16 pin DTC, I get codes 17 and 26, so it is probably the O2 sensor that is causing the light - at least according to some of the lists. Does that sound reasonable for a 94 E320 wagon, which is definitely a 124 with chassis #: 1240921F270482?

I gather from the posts that this car has only one O2 sensor - right?

Thanks!

[lafooy]

I am almost certain that the check engine light only goes on if error/problem exists in the codes you can check with the car's built in switch by the battery . I have some constant codes on pins 8 & 14, but check engine isn't on. I know check engine light works though as it turns on (with all the other dash warning lights) when the key is in acc position.

you have one 02 sensor, it is under the front passenger area ... it screws into the exhaust piping before the catalytic converter and plugs in under front passenger floor mat .... just changed mine a few days ago

However, according to this link those code are for things other than the 02 sensor http://www.peachparts.com/shopforum/showthread.php?t=107630&highlight=ledtool