a150 1.5 petrol 2005 mil on after code read*FIXED*

[beachlife]

Hi there, i had this car in to day after failing it nct(mot) for high co. the thing is it came in with no codes showing? when i tried to scan it with my carman it won't do the 169 model only 168, I then tried it with a friends autoboss which covers the 169 but seems to have no comms with the engine???finally i tried with a small sealy code reader(the little hand held type) and it came up with :heated o2 senor, heater circuit,bank 1 sensor 2 . i cleared the code.
when i rang merc they said they have NEVER sold a rear 02 sensor for this model.Is there any conclusive way to test the heater part of the sensor and any ideas why the mil light is now staying on ? when it had this problem all along? I'm not sure i can trust this scanner(code reader) what is a good scanner for this type of car?
Thanks.

[Ashraf]

Hi

CMT Scanner will talk to this model.

As for your fault code (heater circuit,bank 1 sensor 2) you can test resistance between two same color wires for heater circuit continuity. (Sensor Test)

What was the fault code

1) P0036 Heater Circuit Malfunction ?
2) P0037 Heater Circuit Low ?
3) P0038 Heater Circuit High ?

HTH Ash

[beachlife]

Hi ash, The code was p0036 circuit malfunction, what sort of resistance reading should i be expecting ??

[Ashraf]

Hi

Not sure but, that code indicates you have open circuit on heater circuit side.

Just to be sure check on front sensor and you will get some idea what resistance should it be

HTH Ash

[beachlife]

Okay,That's cool It will be back during the week i'll check it then,
What's a CMT scanner?? who sells them?
Thanks.

[Ashraf]

Hi

Have a look in here.


http://www.v-techuk.com/english/products/diagnostic.asp


Ash

[beachlife]

Hi there, fitted a new sensor today and all is well,genuine mercedes. FIXED.
thanks for the quick replies,
cheers.

[Ashraf]

Hi

Glad you have sorted   

Ash

[manicmotors]

beachlife
am i reading this correctly?
the co was high and a rear lambda sensor cured the fault?
martin

[beachlife]

yes manic, strange as it may sound. there was only one fault code(rear sensor heater circuit) so replaced it. i had a feeling that this car does not get any long runs(housewifes car,school run etc...) so i took it for a drive up the motorway for about 2 hours came back put it on the gas analyzer and its fine.So i'm not sure if the rear lambda CURED the fault ,just that it needed to be replaced to put out the mil