Date: Thu, 12 Mar 2015 10:50:13 -0700
Reply-To: John Goubeaux <john@UCSB.EDU>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: John Goubeaux <john@UCSB.EDU>
Organization: UCSB
Subject: Re: No Start Scenario
In-Reply-To: <5500C997.2000402@cox.net>
Content-type: text/plain; charset=utf-8; format=flowed
On 3/11/15 4:02 PM, mark drillock wrote:
> The fuel pump is at the far end of a chain of several things that all
> must happen before the fuel pump will run when it is supposed to. In
> my experience only rarely is the cause the pump itself or the relay
> for the pump.
>
> Both relays have to be installed and working for the fuel pump to run
> like it is supposed to. The ECU controls the FP relay by switching its
> ground pin on/off.
>
> What you are experiencing is pretty common these days. One cause is a
> burned out pin D15 of the main panel. This is the pin that the key
> switch powers on to run the ignition coil and trigger the power relays
> for the ECU and fuel pump. It is a black wire and you can measure at
> the ignition coil black wires to see that the key-on power is reaching
> the coil.
I replaced the ignition switch and then I checked for current at the
ignition coil black wires ( terminal 15 ) and do NOT get any current
there at all with key-on-power. So looks like you nailed it ( again ) Mark !
So, when you say: "burned out pin D15 of the main panel." you mean
it's disconnected, corroded or ? What's my next step? I assume open the
panel and investigate ? Any pointers on what to look for etc. at this
point. I assume that current flows from the D15 pin directly back to
the #15 connector at the coil, right ? OR is there anything in between ?
Doesn't look like I'm gonna need those relays that I ordered !
Thanks again -john
> From there the smaller of the black wires carries power over to the 2
> relay sockets to enable them. That is what you found missing, the
> enabling voltage at pin 86 of the FP relay socket. Check the black
> wires for voltage when the key is on.
>
> Mark
>
>
> John Goubeaux wrote:
>> Hi Guys,
>>
>> 2WD 90 2.1
>>
>> I'm trbl shooting a NO start scenario.
>>
>> Starter cranks over the engine just fine. I Do NOT hear the FuelPump pre
>> cycle - at all - when ignition goes to the ON stage SO I headed in that
>> direction and used the FuelPump Relay diagnose from this page:
>> http://www.vanagonparts.com/fuel_pump_relay.html - which BTW looks like
>> it is derived from the "Dijifant Guide"
>>
>> 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, 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.
>>
>> 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 ?
>>
>> Thanks for any advice
>>
>> PS:I know there is a lot of info online already on this topic, BUT I've
>> yet to find a thorough diagnostic step by step with ALL the needed info.
>>
>> -john
>>
>>
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