Date: Sun, 20 Apr 2008 03:53:16 -0700
Reply-To: Mark Drillock <drillock@EARTHLINK.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Mark Drillock <drillock@EARTHLINK.NET>
Subject: Re: '86 Westy cranking trouble
In-Reply-To: <5F8C30BA-D1E7-4475-B697-6F7F7FE4D4D2@WESTAL.NET>
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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"
>