Date: Sat, 26 Jan 2013 17:54:50 -0800
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: Ignition Switch "Su" Power
In-Reply-To: <CAB2Rwfif5D-x3-kuGDLCFTpTr+sEVsbod8Qmdc1nqWnkEehL7A@mail.gmail.com>
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The wiring swap stuff just gets more fun the more you do it.
I would probably fuse the heavy load wire prior to a relay, rather than
after.
I have only ever seen one case of this ..
but I swear , one time in an early vanagon ..might have been an 82
diesel ...
a relay shorted or failed internally,
and it routed hot power to the ground side of numerous things ..frying a
bunch of wires.
Highly unlikely for that to occur ..
but it's one more device fuse protected.
you always want fuse or circuit breaker protection right after the
source of the power ..immediately after ..
whateve wire runs or devices prior to the fuse are not protected.
Some people do not recognize that factor.
I have an 85 Vanagon with the entire interior and all windows blown out
from a fire ..
Someone ran hot wires from the battery to a soundsystem Big Amp under
the back seat ..
and it was fused there.
the hot wires ....tangled under the floor rug ..
unfused, ...since that's upstream of the fuse ..
shorted, sparked, started a real fire.
the guy didn't have a fire extinguisher ..
and no way to disconnect the battery like 'right now' ..
all he could do was call 911 and get out of the van and watch it burn to
a crisp..
all due to incorrect fuse protection location.
so always fuse closer to the source of the power .
in gernal, Japanese cars are very very good about fuse protection ..
commonly have regular fuses and Slow Blow Fuses ..
and even fusable links..
you can even buy 'fusable link wire' ...wire that is designed to fail
just like a fuse does. ..
rather than fry other things.
There is huge power in the electricity contained in a car battery ...
Fires are as likely to start for electrical reasons as for fuel reasons..
perhaps even more so.
scott
www.turbovans.com
On 1/26/2013 5:29 PM, neil n wrote:
> I've recently been studying the Bentley a lot. I see that; unfused 15 circuits.
>
> The A3 Bentley does not show a fuse for the power supply relay and
> circuit. I installed a10A fuse at the wire from 87 of the power supply
> relay. Maybe the fuse should be installed pre relay on 30? Anyhow....
> The HO2S relay and fuel pump circuit share on fuse.
>
> Thanks for the insights to the Subaru world.
>
> There's so much to this swap stuff!
>
> Neil.
>
>
>
> On Sat, Jan 26, 2013 at 3:50 PM, Scott Daniel - Turbovans
> <scottdaniel@turbovans.com> wrote:
>
>> ok..
>> you're powerng the ecu directly from the ign switch.
>> and the coil through a relay.
>> sure, give it a shot.
>>
>> tell me this ..
>> do you have your main power input to the ecu fused ?
>>
>> ( as you probaby know, the 15 circuit on a vanagon is not fused at all,
>> anywhere.. Most cars are like this on the igntion circuit btw ...or at
>> least before cars got crazy complicated. )
>>
>> In subaru conversions both types of power are fused ...
>>
>> The reason I mention this is ...
>> how much current do you figure your ECU draws ?
>> I wouldn't know myself really,
>> but I can get an idea from ( same year as you ) ...93 / 94 Subaru wiring
>> diagrams and conversion information.
>>
>> One diagram I have shows the 'main hot' coming out of the Main Relay to
>> power the ecu with a 30 amp fuse.
>> You have a main relay there ...so that wire probably is the high current
>> feed to your ecu.
>>
>> As your drawing is currently ..
>> the 'other' power feed to the ecu is unfused. ..
>>
>> so that is 3 'powers' ..1 to coil, 1 small one to ecu, and one large one to
>> the ecu via the main relay.
> --
> Neil n
>
> 65 kb image Myford Ready For Assembly http://tinyurl.com/64sx4rp
>
> '88 Slate Blue Westy to be named.
>
> '81 VanaJetta 2.0 "Jaco" http://tubaneil.googlepages.com/
>
> Vanagon VAG Gas I4/VR Swap Google Group:
>
> http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-engines
>
