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Home >> Isuzu >> 2004 >> Axiom Base, 4WD >> Repair and Diagnosis >> Engine Performance >> System >> Engine DRIVEABILITY And Emissions - DTC P0452 To P1221 >> DTC P0463: Fuel Level Sensor Circuit High Input >> Test Description
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Test Description

Number(s) below refer to the step number(s) on the Diagnostic Chart.

  1. 9. Equates the resistance values at various float positions to the following fuel gauge readings:
DTC P0463 - FUEL LEVEL SENSOR CIRCUIT HIGH INPUT

Step Action Values Yes No
1 Was the "On-Board Diagnostic (OBDII) System Check" performed? - Go to Step 2 Go to On-Board Diagnostic (OBD-II) System Check
2
  1. Disconnected the fuel level sensor harness from its connector at the fuel tank.
  2. Ignition "ON", Engine "OFF".
  3. Using a DVM, measure the voltage between the sensor harness positive and ground wires.
Is the voltage approximately equal to the specified value?		 5 V Go to Step 10 Go to Step 3
3 With the negative DVM lead connected to ground, use the positive DVM lead to probe the sensor ground wire with the harness still disconnected.
Does the DVM indicate a short to a voltage source?		 - Go to Step 4 Go to Step 5
4 Repair short to voltage between the sensor and the ECM.
Is the action complete?		 - Verify repair -
5 With the negative DVM lead connected to ground, use the positive DVM lead to probe the sensor signal wire with the harness still disconnected.
Does the DVM indicate a voltage greater than the specified value?		 5 V Go to Step 4 Go to Step 6
6 Repair open circuit between the ECM connector and the fuel level sensor.
Is the action complete?		 - Verify repair Go to Step 10
7 Install the test ECM.
Program the test ECM (Immobilizer system). Refer to IMMOBILIZER SYSTEM .
Check the OBD-II test for following condition:
  1. When the ignition is "ON", turn on the MIL and RPL (RPL is put out after 3 seconds).
  2. When the engine is started.

Did the DTC disappear?		 - Go to Step 8 Go to Step 2
8 Replace the original ECM.
Check the poor connection between the ECM and ECM connector.
Recheck the OBD -II test again.
When the engine is started.
Did the DTC disappear?		 - Verify repair Go to Step 9
9 Disconnect the ABS control unit connector.
Reprogramming the original ECM. (Engine control and Immobilizer control)
Recheck the OBD -II.
Did the DTC disappear?		 - Verify repair Go to Step 10
10 Replace the ECM.
Recheck the OBD -II test again.
Did the DTC disappear?		 - Verify repair Refer to Diagnostic Aids 
11 Remove the fuel level sensor and check the following:
  1. Does the arm move freely?
  2. Are the wire leads shorted together?
  3. Do the resistance values match the specification chart?

Was a problem found?		 - Go to Step 12 Go to Step 8
12 Replace the fuel level sensor.
Is the repair complete?		 - Verify repair -
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