Hello, I have a 2000 C280 with the CEL on. I pulled the codes and got a p0135 and p0410 code. I changed the 02 sensor and cleared the codes. 2 days later the ecu had a p0410 code pending. eventually the cel returned with a p0410 and a p0135. First the car has 275 K and I changed the wrong 02 sensor. Since the codes are now reversed with the p0410 showing first I nam asking for direction. I checked the air pump and there doesn't seem to be any loose or broken vac lines. would a bad 02 sensor cause a p0410 code to register first?
I intend to replace the 02 sensor since it is probably close to the original.

PS - I searched this board for insight but figured that I would ask again.

Thanks in advance

Rob

Code 135 is an O2 sensor heater circuit malfunction.
This could well be the cause of code 410, as an O2 sensor will not warm up enough at idle, to produce a good signal/response.

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2007 C 230 Sport.

Manny, thanks for the response. I figure that I will replace the 02 sensor on Bank 1 Pos 1 and go from there. The air pump seems to be working as I listend to it run this morning during start up. I'm hoping that the 02 sensor is lazy and needs replacemnt. I'm still curious though about the sequence of reporting. After resetting the codes the car passed all 02 diagnostics as per the OBD scanner. The only 2 areas that took significant time to report was the secondary air section and the catalyst section. After both sections completed their testing the 0410 code was stored as pending. When the CEL came on the codes were in the following sequence.

Code 1 ( Freeze Frame) P0410
Code 2 P0135

Is there any way that a DIY guy can test the Air injection system ?

Thanks

Rob

The sequence is as follows:
Upon start-up, the airpump engages for a short while.
When this happens, the O2 sensor should immediately report a " Lean " signal.
If, as in your case, the O2 sensor is not producing a high-voltage signal ( " Rich "), to begin with, this could set code 410.
Normally ( on most cars ) codes will set in the order in which they occur.

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2007 C 230 Sport.

thanks again. New 02 is on order. Is there a tool that is relativley inexpensive that can pull real time data from these cars? I would like to see the interaction of the sensors during the cars operation.

Rob

If you have a DVOM, you can back-probe into the sensor signalwire and see what is happening.
I use a safety pin to back-probe right into the connector, rather than pierce the wire insulation.
FWIW, I recently purchased this scanner:
http://www.autorepairmanuals.biz/site/573683/product/CP9180
but have not used it much as of today.

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2007 C 230 Sport.

Warm-up engine temp over 80c turn on your air pump for 60 sec and watch your both side O2 sensor before cat MUST drop below 40mV.

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MB STARS Master Guild Technician,17 years MB tech
14 years independent shop owner

Thanks for the information. How do you start the Air injection system up manually?

Thanks Rob.