Date:         Wed, 11 Mar 2015 14:44:45 -0700
Reply-To:     Neil N <musomuso@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Neil N <musomuso@GMAIL.COM>
Subject:      Re: No Start Scenario
Comments: To: John Goubeaux <john@ucsb.edu>
In-Reply-To:  <5500B0DF.9030002@ucsb.edu>
Content-Type: text/plain; charset=UTF-8

On 3/11/15, John Goubeaux <john@ucsb.edu> wrote:

> So starting with the FP Relay:
>
> I pulled the Relay
> I confirmed that # 30 has battery current BUT  # 86 does NOT
> I jumped  #87 with #30 and FP whirls away ( so FP does work )
> I checked continuity with #85 to ground with engine cranking and I have
> continuity ( So ECU is going to ground )

So engine didn't start while FP relay was jumped right?
Ground being present at FP relay while cranking engine indicates
that the ECU is supplying ground, as it should.
Assuming ignition was off, that is correct; you should not see + power at FP 86


> So, what does the fact that I do NOT get battery current from # 86 mean
> ? And is this from the Ignition switch? (  or should I have left the
> relay plugged in while testing ?)  There is No indication in the steps
> other than to "diagnose the circuit". I'm unclear IF that circuit is
> energized from the FI Relay OR the ignition switch. So this is where I
> am stuck.


FP 86 (+) is supplied from ign. switch 15. So, you should see voltage
there, key turned to ign. on, even if engine not running. ECU supplies
ground to FP relay which energizes relay.
I'm unclear as to whether or not + at ECU relay 86 is supplied to ECU
23 and exactly what that is for. Mark Drillock has posted on the newer
5 pin ECU relay.

> I've got a new ignition switch and relays on the way so can do some
> swapping out AND intend to replace the ignition switch anyway as it IS old.
>
> Can I assume that at this point the ECU and FP are OK and that it's
> likely a relay, ignition switch, and or connections in between ?

An ign. switch is a handy spare part. The fault may very well lie at
ignition switch
or points in between.

Check and clean all grounds. Including strap between drivetrain and
frame, front of transmission and at battery post and to frame.

Since the ECU is what turns on the FP relay, I'd start with all grounds to ECU.


--
Neil n

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