[V8] New O2 Sensor- Whhhhaaaatt

[dsaad at icehouse.net]

I am with Steve here -
those resistance readings sound more like switch maximum contact values - also
meaning the switch is closed at "room temp".
This is exactly the confusion I was talking about.

Any RTD (Restance Thermal Device) I have come across is at least 100 ohms. Most
automotive sensors are in the 250 ohm to 8K ohm range.

There will also be a direct relationship of resistance to temperature, but the
service manuals usually give voltage readings.

Dave


Quoting "Buchholz, Steven" <Steven.Buchholz at kla-tencor.com>:

> ... you can infer the values from the OBD section on the EFI system.  The
> coolant temp sensor is one of the ten parameters that the ECU logs.  I can
> read the values out using ProDiag ... should also be possible from VAG-COM.
> The advantage of using this method is that you see the value that the ECU
> sees ... and you don't get your hands dirty ... or burned!
>
> It is a bummer to hear that the value is so low ... are you sure this is
> right Ingo?  Resistance measurement in such a low range is prone to errors
> due to connector resistance.
>
> Steve B
> San José, CA (USA)
> >
> > Yes to the sensor on the back of the head.  The initial Service
> > training document even has a graphic on the proper sensor Ohm
> > readings, which, surprisingly are not in the four book volume.  There
> > it only states that the sensor reading on a 'cold' engine at room
> > temperature should read between 1.5 and 3 Ohms.  (mine read at 1.46 -
> > close enough).  Now I need to check the resistance when it's hot...
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