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Subject:Re: Jetta Power Supply relay questions (Vanagon conversion) PIC of wiring diagram.
From:neil N
Date:Wed, 16 Apr 2008 14:14:21 -0700

Hi Scott.

On Wed, Apr 16, 2008 at 1:21 PM, Scott Daniel - Shazam
<scottdaniel@turbovans.com> wrote:
> Here's what I'm wondering.
>  Is the fuel pump energized by the ECU supplying ground to it, to energize it
>  ? ( like waterboxer vanagons have, and like subaru's have ) .

Yes. The ECU supplies grounds to fuel pump relay as well as other relays.

>  If so, temporarily supply your own ground to make the fuel pump run,
>  Then see if the engine starts.
>
>  OR....just hot wire the fuel pump temporarily and see if the engine then
>  runs.
>  But as long as the ECU is supplying ground to energize the fp relay, the
>  other contacts sure should not be hard to figure out or get right.

I hot wired the FP relay yesterday. I heard it run continuously, and
could hear fuel coming up through lines to fuel rail.

This makes me wonder if FP is running during cranking cycle.

>  '3/86' and the '2' don't make sense to me.
>  The J16 relay looks like a regular 4 contact relay to me, with nothing
>  mysterious about it.
>  Are you resisting moving to the next step ?

Yup! Regular "B flat" (very common key in music) relay, except that it
appears 30 is wired internally to provide + to one side of
electromagnet coil. Pretty sure only 3 connections needed.

Nope!  :^)

Today, I'll be hot wiring FP while cranking to see if that's the issue.

I'll also be making up a push button (temp "on") for starter, so that
will help a lot with trouble shooting.

Thanks very much!

Neil.

>  -----Original Message-----
>  From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
>  neil N
>  Sent: Wednesday, April 16, 2008 12:51 PM
>  To: vanagon@GERRY.VANAGON.COM
>  Subject: Jetta Power Supply relay questions (Vanagon conversion) PIC of
>  wiring diagram.
>
>  Hi all.
>
>  I still have a no start on my conversion, so am double checking the
>  wiring to added relays for Jetta ABA OBD1 into my Vanagon.
>
>  In this image from Bentley (Jetta):
>
>  http://tubaneil.googlepages.com/jettafinal1.jpg/jettafinal1-full;init:.jpg
>
>  there are two connections " 3/86 " and " 2 " near relay, that I'm curious
>  about.
>
>  2 appears to connect with "malfunction" light on dash.
>
>  + from ignition switch (15) goes to 3/86, but 86A is negative from
>  ECU. There is only an 86 on relay.
>
>  I would think that they don't shard the connection!
>
>  And..... it appears that 30 is supplying + to 85 of relay internally,
>  so why would there be a need for "keyed" + to relay?? Relay should be
>  "turned on" by negative from ECU.
>
>  I'm confused.
>
>  I guess the simple question is, as per the diagram, do 3/86 and 2
>  actually connect to the relay?
>
>  Thanks for any help!
>
>  Neil.
>