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1stgen!!!
07-08-2011, 08:32 PM
hey guys
i'm having alittle problem with my reserve fuel light, it never turns off!
what is going on with my fuel float?

thanks for any help

Hazwan
07-08-2011, 09:22 PM
Mine never works haha but is your fuel gauge working fine?

1stgen!!!
07-09-2011, 09:16 AM
sometimes when fill up the tank, he marks empty...then suddenly it returns to working...

reYmo
07-09-2011, 10:28 AM
as far as I know, there is a separate device for fuel light, which embedded to fuel float.
or, there is another small float attached to fuel float.
that little float must be stuck, take them out of your fuel tank to inspect.
sometimes a little knock-knock at the fuel tank solve it.

1GCustomAccord
07-09-2011, 09:48 PM
Before changing the thermistor or complete sending unit you first need to check the system. Test the low fuel lamp by grounding the thermistor wire under the back seat with the key in ignition, (i think is a green/red wire) if the lamp lights up, the thermistor is bad, if not, the lamp is burnt or the wire is broken somewhere.

The sending unit in the fuel tank is in fact 2 devices, a float with a resistor attached, and a THERMISTOR (basically a resistor in a bullet-shaped case) for the low fuel light.

The working principle of a thermistor is temperature: When the fuel is high, the thermistor is submerged and is cold, having very high resistance (around 1500 ohms @ 25 celsius) so no current flow. When the fuel gets low enough, the thermister is not submerged in fuel and the temperature rises, so resistance drops, so current flows, so lamp lights up, so you go to the nearest gas station.
:)

Hazwan
07-09-2011, 10:45 PM
Woot thanks for the info! I never bothered to check why its not working before haha.

reYmo
07-10-2011, 10:00 AM
Before changing the thermistor or complete sending unit you first need to check the system. Test the low fuel lamp by grounding the thermistor wire under the back seat with the key in ignition, (i think is a green/red wire) if the lamp lights up, the thermistor is bad, if not, the lamp is burnt or the wire is broken somewhere.

The sending unit in the fuel tank is in fact 2 devices, a float with a resistor attached, and a THERMISTOR (basically a resistor in a bullet-shaped case) for the low fuel light.

The working principle of a thermistor is temperature: When the fuel is high, the thermistor is submerged and is cold, having very high resistance (around 1500 ohms @ 25 celsius) so no current flow. When the fuel gets low enough, the thermister is not submerged in fuel and the temperature rises, so resistance drops, so current flows, so lamp lights up, so you go to the nearest gas station.
:)
Genius!!:thumbup:
I never check mine also....maybe because I never run out of fuel. but since I had this car, that light NEVER goes on...
Thanks for the info!!

1stgen!!!
07-10-2011, 06:41 PM
life is funny someguys never seen the light on
and i always see mine on... at night that strong red light ,that haven't dim function, obfuscates me...

1GCustomAccord
07-10-2011, 10:52 PM
Welcome guys! :cool:

Hazwan
01-02-2012, 02:02 AM
So I've decided to drop the tank and see whats up with my FUEL light not coming on even after I've drained the tank.

The thermistor broke into pieces ><

Does anybody know if a regular thermistor would work as a replacement?

Hazwan
01-03-2012, 02:34 PM
Screw fixing the original sensor! I tried everything I could to replace the thermistor with stuffs that I have lying around and it still wouldn't work.

I've decided to built another circuit to work off the float level, turning on the lamp around < 8 liters left, just like how the stock system works.

2ndGenGuy
01-03-2012, 05:59 PM
Screw fixing the original sensor! I tried everything I could to replace the thermistor with stuffs that I have lying around and it still wouldn't work.

I've decided to built another circuit to work off the float level, turning on the lamp around < 8 liters left, just like how the stock system works.

PICS and HOW TO! :gun:

Hazwan
01-03-2012, 10:04 PM
No that circuit doesn't work -.-

It won't go off even when the tank is full. Well when I had the sensor shorted so the gauge would read full haaah!

Now back to finding another circuit that would work.