Facelift fuel tank senders

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winx
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Post Tue Jul 02, 2013 10:24 pm

I am trying to hook up a digital dash to read the fuel level in my tank. Am I right in thinking the RH level sender reads the level (59 ohms empty 4.6 full) and the LH side one drives the low fuel level light on the dash?

Currently using the brown/green and brown wires from the plug under the LH rear seat to feed it with 5v then a divider to feed the dash with a 0-5v signal to tell it how full it is...

Thanks
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Brianmoooore
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Post Tue Jul 02, 2013 11:50 pm

The levels in the two halves of the tank can vary considerably, so a level sensor is needed in each side of the tank. Both level sensors are connected in series, to give a total empty resistance of about 120 ohms.
Grrrmachine
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Post Wed Jul 03, 2013 5:57 am

I took my signal from behind the dash cluster for fuel gauge readings, as the two senders' signals are combined at that point, as Brian explained.
winx
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Joined: Wed Jul 30, 2008 11:00 pm
Location: almost certainly not working on my E30...

Post Wed Jul 03, 2013 10:29 am

Thanks guys, I'll give that a go. So close with this dash, just the fuel gauge and speedo to sort...