[V8] Coolant Temp Sensor Values (was New O2 Sensor- Whhhhaaaatt)

[dsaad at icehouse.net]

I think the sensor at the right rear head (for the ECU) and the sensor at the
left front head (for the guage) are the same part number - right?

If so, maybe there is a resistance/voltage chart for this sensor?
I seem to recall using this info to test the ECU sensor.

I believe the Service Training Manual is the correct source of information for
this one.

Dave


Quoting Ingo Rautenberg <i.rautenberg at waratap.com>:

> Hmm.  I have conflicting values here, guys.  I checked the Four
> volume manual and under the fuel or ignition section I confirmed it
> said that the coolant temp sensor at the back of the head should read
> between 1.46 and 3 Ohms (not k Ohms).  But according to the earlier-
> released Service Training Book with the graphic scale chart, this
> MUST be a typo.
>
>  From what I can discern, according to this, the values should be ~
> 2k to 3k at room temperature.  This value drops to ~90 Ohms at 130 C
> and rises to ~ 6k at 0 C / 32 F and up to 13k at -22 F / -30 C
>
> Anyone want to confirm?
>
> On Jul 17, 2006, at 2:56 PM, Ingo Rautenberg wrote:
>
> > Steve,
> >
> > Since i'm at work right now I can't verify.  But that's what I recall
> > from the Factory Manual reading of yesterday.  Yeah, I looked twice,
> > too.  I thought the resistance value would/ should be much higher...
> >
> > Will recheck when I get home.
> >
> > On Jul 17, 2006, at 2:33 PM, Buchholz, Steven wrote:
> >
> >> ... 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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