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Subject:Re: Working ranges for Temp sensor and AFM
From:James Creech
Date:Tue, 3 Apr 2001 22:30:18 -0400

The Bentley graph shows, for both sensors (approx.):

0C / 32F    5-6k ohms
10 / 50       3.5-4k
20 / 68       2.5-3k
30 / 86       1.5-2k
40 / 104     1-1.5k
50 / 122     700-900
60 / 140     550-650
70 / 158     400-500
80 / 176     300-370
90 / 194     220-290
100 / 212   180-220

The AFM pin resistances are (4 on left to 1 on far right, looking into the
pin housing):

3 and 4    500-1000 ohms (total resistance of the pot)
2 and 3    ohms fluctuate as vane is opened (resistance thru wiper)
1 and 4    ohms according to table above (intake air temp sensor - temp 1)

----- Original Message -----
From: David Beierl <dbeierl@ATTGLOBAL.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, April 03, 2001 7:13 PM
Subject: Re: Working ranges for Temp sensor and AFM

> Ah -- gotcha.  I'll answer tomorrow unless someone else does, don't have
> Bentley with me right now.  At equal temperatures, though, the Temp I
> sensor in the AFM should measure about the same as the Temp II sensor in
> the motor, the specification is the same.  Very roughly, from several
> kilohms cold to a few hundred ohms or less hot.
>
> If you measure voltages, though, the AFM should run smoothly from zero to
> about five volts (with ECU connected and ignition on) as you open the
> flap.   I don't have pinouts, but there is a ground lead, a +5 volts lead,
> the wiper lead, and either one or two for the Temp I sensor.  The temp II
> sensor should be ?a volt or two? cold, and down around one or two tenths
of
> a volt warm.
>
> david
>
>
>
> At 03:35 AM 4/3/2001, Javier wrote:
> >I am trying to help a friend with his van; we disconnected the
Temperature
> >sensor after feeling that idle was errant, and,.... it worked (although
with
> >slighty high rpm�s).
> >That is why I would like to know in which ranges (ohms) does this sensor
> >work in order to find if this is malfunctioning and so, we will replace
it.
> >(Will use a multitester)
> >
> >Regarding the AFM (Air Flow Meter), it is my friend who thinks it is the
> >defective one.
>
> David Beierl - dbeierl@attglobal.net