Scubbs

Hello,

I've done a lot of searching and here is what I discovered so far. I have an error code of P0134 which I found to be:

O2 sensor circuit - No activity detected (Bank 1 Sensor 1)

What I can't find is which O2 sensor is this and where is it located? Plan to replace. I have an 03 C320. Thanks in advance!!

ATL_MB

If no activity is detected, the sensor is likely disconnected or the wire has been cut or shorted. Look for the sensor with the loose / broken wire.

Sensors are numbered sequentially from the engine, so sensor 1 is closest to the engine, before the cat. Not sure if Bank 1 is the left or right side of the engine.

Scubbs

I'm going to check now thank you for the info. Anyone know which side this O2 is on?

Dingleberry

Bank 1 is passenger. If the O2 sensor is in fact connected then it is obviously trashed and needs to be replaced.

Glyn M Ruck

Please complete your profile. Passenger side where?? US, UK?? Do you mean RHS?

Dingleberry

Everything is assumed to be U.S unless otherwise stated. This should be obvious because only the U.S is the most important nation in the world.

Glyn M Ruck

I see

FrankW

bank 1 = cylinder 1-3
bank 2 = cylinder 4-6

doesn't matter which side the steering wheel is the cylinder location is not changed.

Glyn M Ruck

Correct - but the passenger side does - see post I'm always amused at people saying I'm going to do something in the autumn or the summer - The autumn or the summer where? Northern or Southern hemisphere. I guess my global job made me picky.

Scubbs

Updated profile and yes I'm in the U.S. Thank you everyone! I'm going to take a look now.

Scubbs

Well, looks like wires and connecter are ok so I guess the O2 sensor is dead in the water. The car has almost 75k miles and sound like that is when they start going bad. Going to order one. One more question, Online part stores list the O2's right side and left side. I'm guessing left side is the passenger side?

Glyn M Ruck

LHS = Drivers side USA - and to confuse you here are the P/Ns as listed by Benz for C320

0015400717 001 L OXYGEN SENSOR LEFT,UPSTREAM CATALYTIC CONVERTER
0015408717 001 R OXYGEN SENSOR LEFT,UPSTREAM CATALYTIC CONVERTER
0015405017 001 OXYGEN SENSOR RIGHT,UPSTREAM CATALYTIC CONVERTER
0015404617 001 OXYGEN SENSOR LEFT,DOWNSTREAM CATALYTIC CONVERTER
0015404617 001 OXYGEN SENSOR RIGHT,DOWNSTREAM CATALYTIC CONVERTER

Scubbs

OK, SO Bank 1, Sensor 1 is 0015405017? (USA)

Sorry for the newbie stuff.

Dingleberry

Just out of curiosity, why are there two P/Ns listed for the left upstream O2? Both are labeled as left but one is called R and the other L. Strange

Glyn M Ruck

OBDII/CAN regime dictates that Bank 1 is always the bank that contains Cylinder 1.

The different sensors upstream for "L" & "R" denotes whether the car is Left Hand Drive or Right Hand Drive. I think the only difference in the sensors is the length of the pigtale to clear the steering column & plug into the engine harness.

Scubbs

any trick on loosening a sensor. The DIY says an adjustable wrench but not having much luck.

lars

Lack of room? If so, this could be the moment to invest in a set of crowsfoot wrenches. A crowsfoot looks like an open-end wrench but is very short and fits on the end of a socket extension.

Scubbs

Lack of room to get any strength on it plus it's on there tight!! Never heard of crowsfoot. Thinking of just finding a shop to do a quick swap for me. Probably still charge me a ton for 10 minutes of work.

Glyn M Ruck

These damn things seize up with heat. Strong wrench & FBH (BH = Big Hammer)

Scubbs

Thanks Lars and Glyn!! I would love to put a hammer to it but don’t even know how to hit it. What about a crowsfoot with about 3 feet of extension from up top? anybody try this? so close but yet so far!!!

Scubbs

OH YA, anyone know the metric size of these sensors?

Glyn M Ruck

It's usually 22mm - measure your new one to check. Here is the Merc special tool for American 3/8 ? drives.



Edit - Costs about 20 bucks - available at many online specialty tool suppliers.

lars

The MB tool is like a crowsfoot with more flats. 22 mm sounds right, and yes, it should come out with an extension on top.

krisv420

Glyn M Ruck

Yeah - screwed up the worlds economies - Thank god for China.