2005 Select / SLX 290 - Broken Smart Craft Fuel Gauge

[gizmo22]

Hi fellow CSRs! Hoping to get some help so I stop pulling my hair out.

100 gallons of fuel in a 2005 Select 290, but gauge still reads empty. Foolishly assumed it was a failed sending unit, so swapped that. Only after swapping it (and still reading empty) did I put a multimeter on the wires to see it's not getting power.

• Boat is twin 5.7 350 MPI
• Tachs, engine temp, trim, oil pressure gauges all work.
• Original gauges (Sea Ray badged precursors to SC100 I believe)

The boat has undergone a repower so I cannot rule out that a 10 pin connector was left disconnected. Some searching here and a few other forums lead me to think it was a cable disconnected in the bilge, but the manual I have doesn't show any electrical connection between the two (manual shows harness runs from sending unit to starboard gunwale then forward to the helm).

 

[Lazy Daze]

Is the fuel level showing properly in the Smartcraft gauge but NOT on the "normal" looking fuel gauge?

Test the sending unit using OHMS, not volts. Remove the pink wire (or quick connect) and put your meter between the sending wire and ground. If the sending unit is working, you should at reading between about 33 and 240 ohms, depending on where your fuel level is (33ohms would indicate full). If you get no reading, you may have a bad ground - run a temporary ground to the sender and retry.

Next, short the sending wire and ground together - with the key "on", your gauge should go to full.

You might try a SC gauge system reset - I always forget how to do that and I would need to look in the SC manual, myself. Check your SC manual on how to do that.