Low fuel light still on with full tank of gas - Toyota Nation Forum : Toyota Car and Truck Forums

Matt94MR2 · 08-23-2010, 05:03 PM

I noticed my low fuel light turned on a little earlier then normal yesterday. I filled up at the gas station and it took less then 9 gallons to fill the tank. The low fuel light is still illuminated even after I have driven it for a day with an indicated full tank of gas. A few things that may be related:
1) I recently swapped over to a gauge cluster w/ tach but it has been working fine for a couple weeks now.
2) I swapped out the stock bulbs for some LED lights from superbrightleds about two days ago.
Everything seemed to be working fine until yesterday. I am leaning toward the LED lights having something to do with it but wanted to get some feedback before I pull out the gauge cluster yet again.

cipher93 · 08-23-2010, 05:54 PM

If I recall correctly, the fuel pressure/level send is different for the tachometer model than it is the non tach, but I thought it caused the level to be off, not the light to be stuck on. What I would try first is to unhook the battery and give it five minutes for the ECU to reset just to see if it does anything (kinda doubt it but worth a shot). I have LEDs in my cluster but they haven't caused issues. They are only the 194s though, not the smaller ones like the fuel light.

94_Rolla_Guy · 08-24-2010, 12:12 AM

there is a separate sensor in the tank for the low fuel light, if you changed the bulb for the low fuel light to LED i would change it back thats probably your problem

Ive done a no-tach to tach cluster conversion without any problems or difference in fuel reading.

Matt94MR2 · 08-24-2010, 04:13 PM

Thanks for the replies. It looks like the low fuel light indicator also uses a 194 bulb on the tach cluster so I had swapped it to LED. I put the original bulb back in and everything seems to work again. It probably turned on right after I did the install but it was the middle of the day so with the glare of the sun I guess I did not notice it until the following day.

Steelballz · 08-25-2010, 07:42 PM

I have the same problem with the low fuel light in my own.
never changed bulbs, but did replace the non-tacho guages for the tacho-version...one day the guage went down to nearly past the empty line at the bottom, and the light is on since...

any idea's?

gideon1331 · 08-25-2010, 11:08 PM

I put in a gauge cluster with a tach in my old Corolla, and then swapped out the bulbs in the tach one with LED's. The fuel light was always on. Pop in a normal bulb for the fuel light, and it worked normally.

There's always enough power flowing through to fully illuminate an LED if it's installed.

I also had to manually adjust the gauge needle several times to get the range right.

Since you haven't installed an LED, I would suspect that the low fuel sensor in the tank is at fault. If you still have the old cluster, try plugging it in and see if the light is always on. If so its the low fuel sensor.

Steelballz · 08-26-2010, 05:37 PM

must be the sensor so, worked fine the last year or so...