Date: Fri, 16 Sep 2022 13:25:01 -0400
Reply-To: Ed McLean <email99@NC.RR.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Ed McLean <email99@NC.RR.COM>
Subject: Re: Coolant light mystery
Content-Type: text/plain; charset=ISO-8859-1
Please check the following Vanagon Technical Service Bulletin clip where it
states the resistance, checked with a digital multimeter, must be between
31K Ohm and 65K Ohm and the coolant concentration must be below 60 percent
for proper Coolant Indicator LED operation.
https://beakerbus.nl/2016/vw-vanagon-technical-service-bulletins/
Technical Bulletin
Group: 90
Number: 92-03
Date: February 29, 1992
Subject: Coolant Indicator LED is Flashing at Normal Temperatures
Model(s): All Models
* refer to appropriate wiring diagram
* disconnect coolant level sensor electrical connector
* check coolant level in coolant reservoir
*** MUST be between MIN and MAX marks
* set digital multimeter, Fluke 83 (US 1119) to ohms function
* check resistance of level sensor with digital multimeter Fluke 83
(US 1119)
*** must be between 31K Ohm and 65K Ohm with correct COOLANT LEVEL
AND COOLANT CONCENTRATION.
NOTE
If coolant resistance is NOT within the above specifications, the
coolant MUST be drained and replaced with NEW coolant mixture of
50 percent water and 50 percent phosphate free coolant antifreeze,
Part No. ZVW 237 104. (In Canada, use Part No. G 001 100). The
mixing should be performed before filling vehicle cooling system.
*****************************************************************
* CAUTION *
* Coolant concentrations of 60 percent or higher will cause the *
* overtemp / low coolant LED to activate. *
End
On Fri, 16 Sep 2022 10:35:38 -0600, OlRivrRat <OlRivrRat@COMCAST.NET> wrote:
> Pretty darn sure that that Coolant Level Probe in the Expansion
Tank
>
>is nothing more sophisticated than a simple Switch > When the Probes are
>
>Submerged > Circuit Closed,, When Coolant Level drops below Probes the
>
>Circuit Opens ~ Any Break in the Circuit will cause the Light to come on ~
>
>There are some Electronic Components within the Circuit that can cause the
>
>light to have some odd behaviors @ times ~ I have seen, in several
different
>
>Vanagons, a condition where if the Igni’Key was turned to Start in a
normal
>
>way (1 continuous move from Off to On to Start) the Light would Stay Lit
>
>but if the Igni’Key was turned to On & left in that position for 10-15
Sec’s
>
>before turning to Start then the Light would go Off & act normally ~
>
>I suspect that D Beierl or Dennis H or others may have an explanation for
>
>that condition ~
>
>
>
>> On 16 Sep , 2022, at 9:33 AM, Ed <email99@NC.RR.COM> wrote:
>>
>> I believe the coolant light circuit measures resistance between the two
pins
>> of the sensor in the plastic tank. If the resistance is out of range
then
>> the light will come on. If the coolant is low or sloshes away from the
>> sensor pins then the light will come on. If the coolant has too much
>> antifreeze then the resistance between the pins will be out of spec and
the
>> light will come on. If the pins are dirty or corroded then they might
read
>> incorrect resistance. There could also be a fault in the wiring for the
>> light that could cause the light to come on. I don't know how to test
the
>> sensor.
>>
>> That all I have.
>>
>>
>>
>> On Fri, 16 Sep 2022 05:57:37 -0700, David McNeely
<davmcneely40@GMAIL.COM>
>> wrote:
>>
>>> Doesn't the coolant light indicate the level of coolant, not the
>>> temperature? I have actually had it come on when I hit a rough spot in
the
>>> road, back some years ago. Bouncy, bouncy, and the light blinked on and
>>> off.
>>>
>>> On Fri, Sep 16, 2022 at 5:16 AM Ed McLean <email99@nc.rr.com> wrote:
>>>
>>>> The original note was a short question asking why the coolant light
would
>>>> turn
>>>> on and off at random times for no apparent reason while the temperature
>>>> gauge
>>>> remained in the normal range.
>>>>