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Subject:Re: "yawn" Another (trivial) Jetta conversion Fuel Pump relay question.... ;^)
From:Mike S
Date:Sat, 19 Apr 2008 07:10:33 -0400

At 09:25 PM 4/18/2008, neil N wrote...
>One thing I had to do, was run a jumper between 30 and 86 on FP relay.
>In Bentley, it shows an internal connection doing the same (though
>there's no "86" shown):
>
>http://tubaneil.googlepages.com/FPrelaydiagram.jpg/FPrelaydiagram-full.jpg

Because the Jetta relay doesn't have an "86" terminal. I doesn't have 4
contacts. It sounds like you're using a generic Bosch type relay (4 or
5 contacts, 2 for coil, 1 for relay arm, 1 or 2 for relay contacts).

>My potentially trivial quesiton:
>
>In diagram on fuel pump relay, there is an icon between 85 and 86. I
>looked inside and there was a resistor.
>
>Why is that resistor there?

You'll have to provide an image, it's not shown (86) on either of the
pictures you posted:
http://tubaneil.googlepages.com/jettafinal1.jpg/jettafinal1-full;init:.jpg
http://tubaneil.googlepages.com/FPrelaydiagram.jpg/FPrelaydiagram-full.jpg

Maybe you're talking about the J17 relay on the second diagram???
Between 85 and 30 is the relay coil (electromagnet). The dashed
horizontal between it and the relay contact arm indicates a mechanical
linkage. Contacts are normally shown with the relay in the unenergized
state, so for this relay, putting power between 85 and 30 would connect
terminals 30 and 87.

The resistor which you may find in parallel (across) the relay coil is
a damping resistor (and is not shown in the diagram), it helps to
reduce the voltage spikes caused when the relay is de-energized, and
the stored magnetic field collapses (like happens with an ignition
coil).