Check Engine Light Codes

[jcasE320]

Hi,
My check engine light came on the other day and the code was # 3 which is LAMBDA Control Inop. Does anyone know where this is located? I've reset the light, but a day later it comes back with the same code. Thanks

[Robert Goodwin]

Never owned a gas car, but I think the lambda control is the O2 (oxygen) sensor. You may want to verify that with someone more knowlegeable than I. Anyone out there have the answer?

[JimVillers]

My understanding is that the Lambda unit controls the quanity of fuel injected based on the O2 sensor and other sensors. Code #2 is for the Oxygen sensor and code #12 for the sensor heating circut. So what is the coe #3 saying? Since I have never seen this code, I would guess it would be the control unit. On the other hand, the code could just mean that the unit is not able to control the fuel because of a cloged fuel filter (low fuel pressure) or a gummy injector. With the cost of modules, I wouldn't invest in a unit without verification from someone with significant experience.

Sorry, but I feel that I am not much help.

[Robert Goodwin]

Looks like Jim has an idea to put us on track here. You don't say which E320 you have, so pointing you to a section of the tech data is difficult. If your car is a 210, I can't help you. I believe all your data is in the WIS. If it is a 124, section 14-5303D takes 4 pages to explain how to replace the Lambda sensor. Lambda is not mentioned one time. It is referred to as the oxygen sensor. You don't mention anything about your car, such as mileage. O2 sensors do not last forever., but Jim identified a different code for it. In order to help clear up some of the confusion, tell us what you are driving, mileage, engine, emmission, fuel system, electrical system work recently done, if any.

[vince]

Lambda control is a condition, not a "unit". The ECU (control unit) reaches Lambda closed-loop control when the control unit is receiving signals from the feedback inputs installed on the car. Those are the oxygen sensor(s) - there may be two - one before the catalyst and one after. My guess is that this code is saying that the ECU cannot interpret the signal it is seeing, therefore it cannot go into closed-loop control. The oxygen sensor(s) may be bad or there may be wiring faults.

[jcasE320]

Well after driving it the other day i rechecked the codes, and now i get #12 which is no voltage to oxygen sensor. So needless to say, it's toast. So far ive found a OEM sensor at Autohaus Arizona for $96.00 and free shipping.

[Robert Goodwin]

How about one of you gas guys wading in on this. It seems to me that if there is no voltage to the O2 sensor, something else up the line is the problem unless the sensor is prone to shorting out. How about it guys? Gals?

[JimVillers]

Bob ... The #12 code indicates that the sensor heating circut has failed (burnt out). That means replace the sensor. Without heating, the sensor could send inconsistant voltages and that could have tripped the code #3. It is godd to start with replacing the O2 sensor as they are cheaper than anything else and they have a finite life.

[Robby Ackerman]

Bob, Jim & Vince,

You guys never cease to amaze me and to think we all shared hot dogs and monkey bread two weeks ago. :cool:

Bob - My fan is running silent. The transmission oil on the shaft did the trick.

[joeym7]

Hi Iwould remove the right frt floor rug and you will see the wiring for the O2 sensor check the connections water collects there and shortsit out you may find a realy bad connector.joeym