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MSNS extra - no fuel pump output!
DaveFJ - 1/3/08 at 07:55 PM

I have been doing battle in the garage once again today and have come up against a new problem....

It would appear that the wire coming from ny MSNS extra to switch on the fuel pumps is not doing anything....

I have connected that wire, via a collision switch, to a relay to run both fuel pumps however it is not showing any output on that wire,
On the megatune it shows 'fuel pump off'

Do I need to switch the pump on somehow from megatune???

I have searched and can find nothing about this...

Cheers

[Edited on 1-3-08 by DaveFJ]


darrens - 2/3/08 at 12:40 AM

also note that MS doesn't provide a 12v output it simply grounds that pin.

Cheers


DaveFJ - 2/3/08 at 11:40 AM

Bugger .. looks like i have interpreted the wiring diagrams wrong

Anyone think it would matter if I used the same +12v to feed the relay as I use to power the hp and lp pumps?


omega 24 v6 - 2/3/08 at 11:57 AM

Should not be a problem at all the coil side of the relay uses very little current. I would however think about getting one with a built in diode on the coil to stop the reverse emf which can be a very high voltage backtracking to the squirt it's self.


DaveFJ - 2/3/08 at 04:08 PM

Hmmmm....

just did some checking and the wire coming from the MS does nothing! it doesn't show any current on or off and it doesn't ground either....

now going to try tracing the fault back to the MS unit BUT this is a nightmare because of where I have mounted it under the scuttle


I bypassed the relay to test the pumps and they work fine. However.... the sealing washers on my HP filter didn't and promptly dumped about 1/2 litre of fuel on my gargae floor...

Just been to halfrauds for new sealing washers and had to pay 6.99 for an assorted box of 100! beleive it or not the local motorfactors don't stock them!

really thought i might get her started this weekend.


DaveFJ - 3/3/08 at 08:54 AM

Ok Ok Ok I admit it... I'm not the best at all this wiggly amps and electrickery nonsense!

I totally failed to read robocog's post properly...

I had been siwtching on the ignition and THEN testing the circuit... When I finally twigged and tested the circuit whilst switching on I found, low and behold, that the wire in question earthed for about 2 seconds....

so now I have that 'fixed'... I have a new problem.....whay is there always another problem???

To cure the leaks I fitted new copper crush washers to the fuel filter and the HP pump but now the HP pump is making a lot of noise and getting warm but not pumping anything... I guess the new washers must be blocking the flow somehow...

so, another evening bathed in petrol beckons! and I still haven't got her started