Trooper LS 4WD V6-3.5L (2002)
Low Fuel Lamp/Indicator: Description and Operation
Circuit Operation
Fuel Gauge
The fuel gauge consists of two intersecting coils wound around a permanent magnet rotor. When voltage from fuse C-10 is applied to the coils, a
magnetic field is generated. This causes the rotor to rotate and the gauge needle to move. The magnetic field is controlled by the engine or powertrain
control module (ECM or PCM) which receives input from the fuel tank unit, at E-22 pin 60.
Low Fuel Warning Light
When there is not an adequate amount of the fuel in the fuel tank, the ECM or PCM will provide ground at E-21 pin 31 and the light will illuminate. The
ECM or PCM determines when the fuel is low based on input received from the fuel tank unit, at E-22 pin 60.