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Check Engine Issue

2K views 11 replies 7 participants last post by  Kestas 
#1 · (Edited)
hi all,
the check engine light is on and I want to know how to check the box which is next to battery.
and if any advice that will be great, the car runs okay and start fine but still has check engine on:confused:
also i wanna know if I pressed the check button in this box while the car is running, is that okay?
thanks
 
#3 ·
Hello Guys,
after I did a check for the check engine light, The Code reading flashed 12 times.
According to this link (E320 16 PIN DTC Charts inc. pin 8, pin 14 - ShopForum)
12 Heated oxygen sensor heater circuit open or circuit short
So what could it be??
Is it mean the O2 sensor or it mean something else?, Since in the same link I mentioned above it says (2 Heated oxygen sensor faulty).
any advice?
Thanks for all
 
#5 ·
Starting in the early 1990s the O2 sensor on a lot of vehicles contained a heating element. This accelerated sensor warm up time so it could provide accurate data to the fuel injection computer sooner.
It sounds like the heating element in your car's sensor has failed. It's also possibly, but unlikely, that the heater circuit connector is unplugged or the wiring is damaged.
As you mention, the car will drive normally because the sensor does warm up anyway within a few minutes. Replacing the sensor will, however, get the system working properly again and reduce HC emissions during cold engine starts. Something we should all be thinking about...
Plus the annoying check engine lamp will turn off.
 
#7 · (Edited)
okay guys let me mention something I forgot to tell; in the same day the check engine light came on my mechanic was doing some fix on my AC and he found a leak coming through the Pressure Switch at Receiver Drier, and he replace it with an used one he bring it from one of the car parking in his shop which was 300E, So any of you guys think that this switch could give me a check engine light or it happened by luck
Note: the car start and run very nice as usual, I see no difference
thanks
 
#9 ·
oxygen sensor / CE light

Hello - not to be a hijacker but this is related / might help. I have had the CE light on so I bought a new universal oxygen sensor off of ebay - supposedly a Bosch unit but it was cheap. It was a pain to install due to the short lead wires. There are 2 white, one black, and one gray.

Does is matter which wire the white goes to? Are the two whites interchangeable. The reason I ask is that the CE light came back on after resetting it. I just got back from radio shack and bought the LED and switch so I will check the code but I wonder if the white wires are the same.

tnks all!
 
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