Diagnostic Aids

Check for poor connection, rubbed-through wire insulation or a broken wire inside insulation. Inspect harness connectors for backed-out terminals, improper mating, broken locks, improperly formed or damaged terminals, poor terminal-to-wire connection, and damaged harness. Using scan tool monitor fuel level display while moving connectors and harness related to fuel sensor. Change in display will indicate problem area.

1. Perform On-Board Diagnostic (OBD) System Check. See BASIC DIAGNOSTIC PROCEDURES article. Read and record FREEZE FRAME and/or FAIL RECORDS data for each DTC set. Go to next step.
2. If a Vehicle Speed Sensor (VSS) DTC P0502 is also set, diagnose it before proceeding. See DTC P0502: VEHICLE SPEED SENSOR (VSS) CIRCUIT/LOW INPUT . If DTC P0502 is not set, go to next step.
3. Remove fuel level sensor from fuel tank. Ensure sensor arm moves freely. If sensor arm does not move freely, replace fuel level sensor. Retest system. If fuel level sensor is okay, go to next step.
4. Connect an analog ohmmeter to fuel level sensor. As arm of sensor is moved, needle on meter should move smoothly. Replace fuel level sensor if operation is not as specified. Retest system. If operation is as specified, go to next step.
5. Using an ohmmeter, measure resistance of fuel level sensor as arm is moved from empty to full positions. Ensure resistance is within specification. See FUEL LEVEL SENSOR RESISTANCE SPECIFICATIONS  table. Replace fuel level sensor if operation is not as specified. If fuel level sensor tests okay, replace PCM. Retest system.
   FUEL LEVEL SENSOR RESISTANCE SPECIFICATIONS
   
   

   Position	Ohms
   E	102.5-120.5
   1/6	73
   1/3	56
   1/2	45
   2/3	36.75
   5/6	30
   F	17-23.5