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Subject:Re: Fuel pressure too high
From:David Beierl
Date:Tue, 6 Mar 2018 16:21:08 -0500

>
> There's no power at the fuel pump, because there is none  at the "Digifant
> Control Unit Relay" (as it is called on page 97.106 (track 34) of the
> Bentley wiring diagram.  I've got power at the Alt B+ terminal.  If I'm
> reading the wiring diagrams correctly, that gets power from the Alt B+
> terminal (on track 5).

Correct.  Both relays should have unswitched power on their respective 30
terminals, fed from the B+ post in the wiring box, fed from alternator B+.

ECU relay is controlled by 15 circuit (ign switch) skinny black wire from
coil positive to ECU relay pin 86.

Fuel pump relay is controlled by ECU grounding its 85 terminal.  86
terminal gets +12V from the fuel injector supply via connection G1 which is
buried inside the harness.

> So have I broken a wire or is there some other
> possibility?

See above

>   Could I have fried the ECU by leaving the ignition on
> overnight to the point of draining the battery?

I'm quite sure not.

Yrs,
d