Date: Sun, 20 Apr 2008 16:43:22 -0700
Reply-To: neil N <musomuso@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: neil N <musomuso@GMAIL.COM>
Subject: Re: '86 Westy cranking trouble
In-Reply-To: <A902C507-A607-43C9-B1AD-ED62A1B036BE@westal.net>
Content-Type: text/plain; charset=ISO-8859-1
Good to see reports on progress.
There is a load of some kind being created when you plug wires you
mentioned back onto coil. Could be a short.
Unhook the battery(s). Make certain the cables are safely seperated
from posts and won't connect.
Use your VOM to check continuity of wires in question.
Disconnect wires (one at a time is best) in question from the system.
Connect one end of wire to ground (frame). With meter set to OHMs
(resistance) put one probe on other end of wire, and one probe to
ground (good quality) IF there's no other electrical components in the
path of the wire, it should read zero.
You can do this with connectsion to/from ECU. Just follow safety
directions on disconnecting harness from ECU if any. I found a safety
pin useful to access female sockets on my Jetta ECU. Regardless,
attach one probe to a given ECU socket, and the other to the other end
of corresponding wire. i.e. big green that goes to coil from ECU.
Doing this may take patience. The numbers on the ECU harness may be
small, and you have to count carefully. Doing this also gives you a
chance to visually inspect stuff at the plug to ignition switch and
fuse/relay panel etc.
Cheers,
Neil.
On Sun, Apr 20, 2008 at 4:21 PM, Dan Hall <elektro@westal.net> wrote:
> My van, an 86 was manufactured in November of '85.
> Last 6 digits of the VIN are 031 388 which would lead us to believe it
> should follow the Bentley for Vanagons up to VIN 055 690.
> However, what I actually find on my van in many cases, more closely fits
> vans from VIN 055 690.
>
> In this particular instance, what I find in the relay box follows the
> diagrams from VIN 055 690. I guess that the folks that record data for
> inclusion in the Bentley had one too many biers on their lunch break or some
> such.
> The power to the coil comes in on a black wire that also splits off to
> provide current for the crankcase ventilation heater unit--that also follows
> Bentley for van from VIN 055 690
>
> This afternoon, I tested the function of the ignition switch and all seems
> well with it.
>
> I then checked for constant voltage on the relays that feeds in on the big
> red wires. Tested OK.
>
> I pulled the 4 smaller gauge wires off poles 1 and 15 on the coil:
> big green goes to Digifant unit.
> little green goes to dash and I believe provides RPM signal to tach and
> dynamic oil pressure system.
> black is switched power from ignition.
> black/yellow feeds power to the relays in the box over the coil. Bentley
> says this should be black/white but mine is black/yellow.
>
> The black power wire showed 12 plus volts.
> I plugged it back onto the coil. Still showed 12 plus volts.
> I then plugged the black/yellow back onto coil-----immediate voltage drop
> to zero. Unplugged it. Voltage back to 12 plus volts.
>
> Plugging in either of the green wires causes the voltage to drop to around
> 8 volts.
>
> I plugged all wire back up to the coil.
>
> Just now, after pondering, I made up a jumper wire to run 12 volts to the
> coil.
> As soon as I reattached the ground strap to the battery, the relays kicked
> in and the fuel pump cycled.
>
> The van started up with no problem. and idled normally.
>
> From that, I reckon I may deduce that my ECU, coil, distributor/Hall sender
> are all OK.
>
> But. I still am not electrically savvy enough to figure out why the
> voltage is dropping with all wires to coil hooked up.
>
> Is this condition indicative or a short to ground somewhere?
>
> Any advice on how to locate it?
>
> thanks,
> Dan Hall
> "Das Boot"
>
>
>
>
>
> Then I tested the black wire for battery voltage with the ignition switch
> on.
> I
>
>
> On Apr 20, 2008, at 11:51 AM, neil N wrote:
>
>
> > Gold info man!
> >
> > I might add, that I found DeOxit to be an *awesome* contact cleaner.
> > There is another product a list member kindly mentioned to me: Rid-ox.
> > It may very similar, or the same.
> >
> > And thanks for clarifying Mark. One of my posts may have been misleading.
> >
> > I quoted from the "newer" version of '86 Digifant wiring.
> >
> > It shows a "keyed" (from 15) black/white wire from coil to "Digijet
> > Control Unit Relay". If I'm not mistaken, power from this wire
> > energizes the relay electromagnetic coil of this relay.
> >
> > But...... I just noticed that they labeled this relay Digijet, but the
> > control unit is Digifant !!
> >
> > Yikes! Bentley '86 wiring diagram shenanigans! --- ;^)
> >
> > Neil.
> >
> >
> >
> > On Sun, Apr 20, 2008 at 3:53 AM, Mark Drillock <drillock@earthlink.net>
> wrote:
> >
> > > As Neil pointed out, there are 2 very different wiring diagrams for 86.
> > > It sound like you have the early version of that wiring. What are the
> > > last 8 digits of your vin# ?
> > >
> > > The 2 engine relays are mislabeled in the wiring diagram for the early
> > > 86!!! This is clear from the fact that the one labeled "fuel pump relay"
> > > is not the one that connects to the fuel pump wiring!
> > >
> > > The relay mislabeled "fuel pump" is really the "power relay" that
> > > supplies everything in the early 86 model.
> > >
> > > Don't worry about relay socket 2 of the main fuse panel, it is empty for
> > > waterboxers. Also, realize that the green wires to/from the coil are for
> > > ignition pulses not power.
> > >
> > > Your use of a jumper wire to test and bypass is a great approach. You
> > > are very close to fixing this I'd guess.
> > >
> > > You are not the first on this list to have a problem in the wiring of
> > > the black twin relay box. Try unplugging the connector to the outside of
> > > the twin relay box. Look closely at both sides of the connectors, clean
> > > if needed and plug back in. It may be as simple as this.
> > >
> > > Power on from the key comes to the engine compartment on a black wire.
> > > On the early diagram there is a labeling error and this wire is labeled
> > > "sw" which is German for black. This error is on page 97.72, top right
> > > at connection pin D15. That is power on from the key which then turns on
> > > the "power relay" which is wrongly labeled "fuel pump relay".
> > >
> > > Again, most of the above is for the early 86 diagram and the wiring in
> > > this area changed drastically after a few months of production. The
> > > later engine harness wiring is simpler and improved.
> > >
> > > Mark
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > > Dan Hall wrote:
> > >
> > >
> > > > I have an '86 Westy Weekender, Wolfsburg edition---pop-top but no
> > > > kitchen.
> > > >
> > > > In the past several weeks, I've had a mysterious, intermittent
> > > > starting problem. The starter works and the engine turns over fine
> > > > but won't crank.
> > > >
> > > > The fuel relays and, thusly, the fuel pump were not cycling when I
> > > > turned the ignition switch.
> > > >
> > > > I discovered that if I lightly tapped on the fuel relay box above the
> > > > coil with the key switched on, the relays would click on and the fuel
> > > > pump would cycle and I'd start it up and off I'd go.
> > > > Thinking it was bad relays, I bought replacements. That solved
> nothing.
> > > > I've since bench tested the relays and they work fine.
> > > >
> > > > The big red wires that supply constant current to the fuel relays have
> > > > 12 volts.
> > > >
> > > > There is a black/yellow wire that runs from the fuel relay to the
> > > > coil. The Bentley says this wire is Black/White but mine is black/
> > > > yellow. With the ignition switch on, I only had 5 to 6 volts on this
> > > > wire. Tap the relay with power on and the relays work, fuel pump
> > > > cycles. Then, I tried to start the van as usual after and it turned
> > > > over fine but would not start. Now, that same black/yellow wire shows
> > > > only 1.2 volts. The relays will not work, even with tapping.
> > > > I plugged in a borrowed Digifant ECU but that did not help the
> > > > situation. I put the old ECU back in.
> > > >
> > > > I ran a jumper wire with 12 volts to that black/yellow wire on the
> > > > coil and the relays and fuel pump all worked nomially.
> > > >
> > > > I had a spare ignition switch and tried that but no joy.
> > > >
> > > > I've studied the wiring diagrams of the Bentley til I'm cross-eyed.
> > > >
> > > > Where does the coil get its voltage supply?
> > > > ----My Bentley shows from a relay in the 2 position on the panel next
> > > > to the fuses in the wiring diagrams but not in the legend of the same
> > > > pages. And I've never had a relay in the 2 postion.
> > > > -----I tested the resistance of the coil and it seems within
> > > > specifications.
> > > >
> > > > What voltage should I have on poles 1 and 15 on the coil with the
> > > > ignition turned on?
> > > >
> > > > I have thought about leaving the 12 volt jumper wire hooked up the
> > > > coil and then try starting it but am holding off til I hear from the
> > > > List.
> > > >
> > > > Any help, advice, guesses would be appreciated.
> > > >
> > > > Dan Hall
> > > > '86 Westy Wolfsburg Weekender
> > > > "Das Boot"
> > > >
> > > >
> > > >
> > >
> > >
> >
> >
> >
> > --
> > Neil Nicholson. 1981 Air Cooled Westfalia - "Jaco"
> >
> > http://web.mac.com/tubaneil
> > http://tubaneil.googlepages.com/
> >
> >
>
>
--
Neil Nicholson. 1981 Air Cooled Westfalia - "Jaco"
http://web.mac.com/tubaneil
http://tubaneil.googlepages.com/
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