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

[Ingo Rautenberg]

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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>
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