Date:         Sun, 12 Aug 2018 17:09:55 -0400
Reply-To:     David Beierl <dbeierl@ATTGLOBAL.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Beierl <dbeierl@ATTGLOBAL.NET>
Subject:      Re: temp gauge not working right...
Comments: To: Dan N <dn92610@gmail.com>
Comments: cc: "Jim. Felder" <jim.felder@gmail.com>
In-Reply-To:  <CAMOH8LKQLAH7HbqWfCugui-PEVy6EfNb8R=gPVYLhkHB9QK58Q@mail.gmail.com>
Content-Type: text/plain; charset="UTF-8"

This is the temp gauge circuit.

+12V--->panel regulator-->10V-->()()()()()-->/\/\/\/\/\-->chassis ground.

()()()()() is the heater inside the gauge that makes the needle move.  It
has approximately 52Ω resistance which doesn't change enough to notice
between cold and working temperature. /\/\/\/\/\/\/\ is the resistance of
the sender which varies with temperature.**

**Sender resistance for OEM sender:
35C ~630Ω, no gauge reading
60C ~265Ω, gauge reads at bottom mark
90C 106Ω, gauge touching low side of LED
100C 82Ω, gauge touching high side of LED
125C 45Ω, gauge near top line and blinker just starts blinking
135C 36Ω, gauge at top line and blinking.

All gauge readings are specified +/- half a needle with input between 9.5
and 10.5 volts.  Most of that tolerance is taken up by the voltage
allowance.

Yrs,
d

On Sun, Aug 12, 2018 at 4:55 PM, David Beierl <dbeierl@attglobal.net> wrote:

> I will measure the voltage at the wide/white instrument cluster connector
>> on pin #6 and ground.... what voltage should I expect to have? - 12V? or
>> 10+ V
>>
>
> With the sender disconnected you should see 9.5-10.5V all the way back to
> the sender.  With sender connected and everything working you'll see a
> range from around two volts to maybe seven volts depending on engine
> temperature.
>
> Yrs,
> d
>