Low Fuel Light Troubleshooting - Will Not Illuminate

[cky3396]

I recently replaced the original fuel sending unit with a URO unit, as the oem unit was reading a higher fuel amount than what was actually present, bench tested to just 60ohms at Empty, and I never saw the Low Fuel light actually turn on.

I have the new URO unit in and it seems to be reading proper fuel level just fine, but I cant force the Low Fuel light on by slowly lifting the sender out of the tank to simulate empty.

ive checked the bulb in the gauge, cleaned the fuel sender harness connectors, and cleaned up the spades/connectors on the back of the fuel gauge best I can... I've bench tested the new URO unit and it passes the Bentley 201-16 "Fuel level sending unit, testing" section.

Can someone check my work here - If I use a jump wire between the corresponding fuel sender harness wires for W and 31, should this force the low fuel light to illuminate?

[Dpmulvan]

Yes or Just switch your meter to continuity attach to W&31 and it should beep when fuel sender is placed in the empty position.

[SpyderMike]

https://forums.pelicanparts.com/porsche-911-technical-forum/1164844-getting-know-fuel-gauge-sender.html

The float must land squarely on the bottom to connect the two low level light contacts.

[cky3396]

thanks guys

Ok so immediately after posting I went ahead and did a little more connector/contact cleaning and tested the URO unit again (which again passed all the Bentley tests)

Good news is, I am now getting the low fuel / reserve fuel light to illuminate on the dash... I even swapped it out for an LED and its actually looking pretty decent when lit.

my fuel tank is in good shape with no deformations or dents and the sender settles nicely, snugs up without issue so im going to assume everything is now situated with this.