Damo V

Honestly mods, this will be the last one I promise

Right, on an ECos, I have 5 wires going to the sender/pump unit,

From the factory
2 of them are for the pump, 1 is live the other earths to body
the other 3 are obviously related to the sender, 1 of them is an earth which is soldered to the earth wire for the pump, the other 2 presumably relate to the fuel level guage and the fuel level warning light?????

see pic



NOW

I have ripped out my old engine loom and replaced with a pectel loom.
I have also run a live and earth for the fuel pump, DIRECT from battery

So the earth for the sender unit is obviously direct to battery now also....

My problem is this;

I have around 3/4 tank of fuel but the needle moves about all over the place when driving and sometomes when stationary after driving, but often settles in the proper position, when it moves about the movement is almost immmediate from one point to another, also the fuel level warning light flicks on and off occasionally....

NOW, have I damaged the sender unit when I fitted my new pump(dont think so)

OR is the direct earth to battery as opposed to body creating interference??

Presumably the fuel light comes on via an earth and the guage goes DOWN when earthed, so maybe something else is causing it to earth out??

But what?

HELP

Damo V

oh and I know we have had a shed load of rain but I dont think that is causing the problem, either way need to sort it as it wasnt doing it before

Damo V

PPS

I can tell you the exact wire colours on that plug if it helps

DazC

iTrader: (1)

Accordidng to my Diagrams, the fuel guage is a normal guage working off measuring resistance to earth and the fuel light goes though something called an auxilliary warning module on a 16 way plug.

The wire from the sender unit for the guage is brown/black and goes to the fuse box wire number 31B-87 on plug M1B.

The wire from the sender unit for the light is brown/green and goes wire number 31B-55 on plug M5D. Then goes out on plug M2B on wire number 31B-55 up to pin 10 of this warning module. The lamp is then triggered by pin 15 of this module on wire number 31B-60 and is brown/green. The system is switched on by an ignition feed and is earthed by this module. The module needs an earth on pin5 and 11 (brown) and also an ignition feed on pin9 (black/yellow).

After all that bollox, i'd try a local chassis earth for the warning lamp and guage sender and see what happens.

Damo V

ah right ... so my theory on the direct to battery earth could be correct?? I mean its not unplausable no??

DazC

iTrader: (1)

It is possible that you're getting a back feed causing this..

Damo V

pukka pukka pukka... at least its simple (hopefully) Oh I'm gonna be a dab hand at removing ECos tanks at this rate