ECM monitors the voltage output signals of the Fuel Level Sensor (FLS) (#1) and the Fuel Sub Sender (#2). The combined resistance of the two sensors in series enables the fuel gage to determine fuel tank level. ECM also uses values from both sensors to determine condition of the EVAP system for leak detection. ECM monitors both fuel level sensors for the conditions of being stuck high or low, and differences between voltages of fuel level sensors. ECM will calculate if voltage deviation of fuel level sensors has exceeded a limit value while driving. This would be interpreted by the ECM as a fault.
The ECM checks the output voltages of both the fuel level sender unit (with the pump motor) #1 and the fuel sub sender unit (without the fuel pump) #2 for a voltage deviation that is under a calculated threshold. If ECM detects a fault a DTC P2065 is set. The Malfunction Indicator Lamp (MIL) turns on and will stay on after 2 consecutive drive cycles.
Item
Detecting Condition
Possible Cause
DTC Strategy
Monitoring fuel sender and fuel sub sender
Poor connection
Shorted signal circuits
Short in signal circuit
Faulty Fuel Sub Sender
Faulty ECM
Enable Conditions
Engine Running
Ignition Voltage > 11V
Threshold value
The difference between fuel sender and fuel sub sender < 2%
Diagnosis Time
Continuous (More than 5 sec.failure for every 10 sec.test)
MIL On Condition
2 Drive Cycles
FLS
Normal Parameter
Float position
8/8
6/8
5/8
3/8
1/8
Warning Lamp ON
Sender-Resistance(?)
6.3±2
28.4±2
66.7±2
73.9±2
Sub Sender-Resistance(?)
11.6±2
55.9±2
77.6±2
100±2
Fuel volume(l)
62.5
(16.5 gal)
48.6
(12.8 gal)
41.7
(11 gal)
27.8
(7.3 gal)
13.9
(3.66 gal)
9.0
(2.4 gal)
Fig 1) Normal data of Fuel Level at idle (41%)
Fig 2) Abnormal data of Fuel Level when fuel level sensor circuit open or short.