Date: Sat, 27 May 2017 17:31:24 -0400
Reply-To: David Beierl <dbeierl@ATTGLOBAL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: David Beierl <dbeierl@ATTGLOBAL.NET>
Subject: Re: Only 5V at Temp II sensor?
In-Reply-To: <CAOXGjpkRSKOJ4J4WAuFnUm02xJyHhL4JXgKXjK4ZuDQsa7WrUg@mail.gmail.com>
Content-Type: text/plain; charset="UTF-8"
Those connectors are readily available at the FLAPS -- look in the H.E.L.P.
section for Bosch-style fuel injection connector pigtails. Probably wrong
color, but otherwise the same.
Yrs,
d
On Sat, May 27, 2017 at 5:15 PM, George Gaudette <gcgaudette@gmail.com>
wrote:
> I failed to reply all -- sorry to David for the double post.
>
> Also, I should add that the 67 ohms resistor is supposed to approximate the
> resistance produced when the sensor senses coolant at normal operating
> temperatures. More or less.
>
> Now once more, with feeling...
>
> Once Mark pointed out my mistake I disconnected the **correct** sender and
> found the positive wire broken at the spade, with lots of corrosion. With
> the wire stripped a little I got 9V to the brown wire's spade (tough to get
> the test lead to touch it well though) and 10V when grounding to a nearby
> ground strap instead.
>
> I hooked up the "67 ohms" resistor that I fashioned and the temp needle
> moved for the first time in a long time -- slightly above dead center over
> the blinkenlight, which I consider normal.
>
> Now I've gotta figure out how to get that orphaned spade out of the
> connector, or replace the connector. The back of the spade is completely
> corroded away.
>
> Anyhow the problem is isolated, so I think I'm well on my way.
>
> Thanks again.
>
> On Sat, May 27, 2017 at 5:12 PM, George Gaudette <gcgaudette@gmail.com>
> wrote:
>
> > Thanks David!
> >
> > Once Mark pointed out my mistake I disconnected the **correct** sender
> and
> > found the positive wire broken at the spade, with lots of corrosion.
> With
> > the wire stripped a little I got 9V to the brown wire's spade (tough to
> get
> > the test lead to touch it well though) and 10V when grounding to a nearby
> > ground strap instead.
> >
> > I hooked up the "67 ohms" resistor that I fashioned and the temp needle
> > moved for the first time in a long time -- slightly above dead center
> over
> > the blinkenlight, which I consider normal.
> >
> > Now I've gotta figure out how to get that orphaned spade out of the
> > connector, or replace the connector. The back of the spade is completely
> > corroded away.
> >
> > Anyhow the problem is isolated, so I think I'm well on my way.
> >
> > Thanks again.
> >
> > -George
> >
> > On Sat, May 27, 2017 at 5:03 PM, David Beierl <dbeierl@attglobal.net>
> > wrote:
> >
> >>
> >>
> >> On Sat, May 27, 2017 at 2:45 PM, George Gaudette <gcgaudette@gmail.com>
> >> wrote:
> >>
> >>> Hi Volks,
> >>>
> >>> '90 water-cooled automatic camper here.
> >>>
> >>
> >> Thank you. :)
> >>
> >>>
> >>> My coolant temp needle stopped moving entirely some time ago. The
> >>> coolant
> >>> blinky light works normally (blinks initially on startup then goes out,
> >>> and
> >>> has recently blinked for low coolant level).
> >>>
> >>
> >> Good. Gauge doesn't have leaky timing cap, and coolant level controller
> >> is successfully simulating overheat in short pulses that activate the
> >> blinker but don't materially affect the gauge itself.
> >>
> >>>
> >>> ...which is to say I hoped to validate that the temp gauge is in
> working
> >>> order (including the wiring to it).
> >>>
> >>> The first thing to do was to check that there is 10V across those
> wires.
> >>> Instead I found there was about 4.9V. I tried with the negative lead
> >>> touching a ground point instead of the brown wire, and got 5.3V.
> >>>
> >>
> >> The ECU supplies five volts to Temp-II through an ?8132 ohm? resistor,
> >> creating a voltage divider with the variable resistance of the Temp-II
> >> sender. This however has nought to do wi' t'gauge -- the problem there
> is
> >> that one of the fly rods has outta skew on t'treadle. Or more likely
> that
> >> the sender or connector is open, of course. It's the black one around
> the
> >> corner from the blue Temp-II sender which is concerned strictly with
> engine
> >> operation. 265 ohms to ground should give you the bottom mark, 35 ohms
> the
> >> beginning of overheat zone and blinking light (light threshold is
> around 42
> >> ohms IIRC). Grounding the sender lead should make the gauge go up like
> a
> >> slow rocket, and if you leave it connected, start smelling hot in a
> minute
> >> or two. No action means either a wiring problem between engine bay and
> >> gauge (but not the panel connector or panel wiring since the low coolant
> >> warning functions) or -- very very unlikely, the gauge heater has gone
> open
> >> or the needle suspension has failed.
> >>
> >> Yrs,
> >> d
> >>
> >
> >
>
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