Dtc 047 Short In Heater Fuel Pump Circuit

Heater & Air Conditioning System. Lexus Is250, Is220D. Gse20 Ale20
Heater. Lexus Is250, Is220D. Gse20 Ale20

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK HARNESS AND CONNECTOR (COMBUSTION HEATER ASSEMBLY - HEATER FUEL PUMP)

CHECK HARNESS AND CONNECTOR (HEATER FUEL PUMP - BODY GROUND)

INSPECT HEATER FUEL PUMP

DTC 047 Short in Heater Fuel Pump Circuit

DTC 048 Heater Fuel Pump Malfunction

DTC 049 Heater Fuel Pump Output Error


DESCRIPTION


DTC No.
DTC Detection Condition
Trouble Area
047
A short is detected in the heater fuel pump circuit.
  1. Wire harness or connector between heater fuel pump and combustion heater assembly
  2. Wire harness or connector between heater fuel pump and body ground
  3. Heater fuel pump
  4. Combustion heater assembly
048
Operation stop of the heater fuel pump is detected.
(Open in the circuit)
  1. Wire harness or connector between combustion heater assembly and heater fuel pump
  2. Wire harness or connector between heater fuel pump and body ground
  3. Heater fuel pump
  4. Combustion heater assembly
049
An error is detected in output to the heater fuel pump.
  1. Wire harness or connector between combustion heater assembly and heater fuel pump
  2. Wire harness or connector between heater fuel pump and body ground
  3. Heater fuel pump
  4. Power heater ECU (combustion heater assembly)

WIRING DIAGRAM


Lexus Is250, Is220D. Gse20 Ale20.Heater.Combustion Type Power Heater System. Dtc 047 Short In Heater Fuel Pump Circuit


INSPECTION PROCEDURE

1.CHECK HARNESS AND CONNECTOR (COMBUSTION HEATER ASSEMBLY - HEATER FUEL PUMP)


    Lexus Is250, Is220D. Gse20 Ale20.Heater.Combustion Type Power Heater System. Dtc 047 Short In Heater Fuel Pump Circuit

  1. Disconnect the connector from the combustion heater assembly.

  1. Disconnect the connector from the heater fuel pump.

  1. Measure the resistance according to the value(s) in the table below.

    Standard resistance:
    Tester connection
    (Symbols)
    		Condition
    		Specified condition
    A51-2 (L) - Q55-2
    		Always
    		Below 1 Ω
    A51-2 (L) - Body ground
    		Always
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2.CHECK HARNESS AND CONNECTOR (HEATER FUEL PUMP - BODY GROUND)


    Lexus Is250, Is220D. Gse20 Ale20.Heater.Combustion Type Power Heater System. Dtc 047 Short In Heater Fuel Pump Circuit

  1. Measure the resistance according to the value(s) in the table below.

    Standard resistance:
    Tester connection
    (Symbols)
    		Condition
    		Specified condition
    Q55-1 - Body ground
    		Always
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.INSPECT HEATER FUEL PUMP


    Lexus Is250, Is220D. Gse20 Ale20.Heater.Combustion Type Power Heater System. Dtc 047 Short In Heater Fuel Pump Circuit

  1. Measure the resistance according to the value(s) in the table below.

    Standard resistance:
    Tester connection
    		Condition
    		Specified condition
    Q55-2 - Q55-1
    		Always
    		9 to 12 Ω

  1. Inspect heater fuel pump operation.

    1. Connect the positive (+) lead from the battery to terminal 2 and the negative (-) lead to terminal 1, and check the pressure of the hose by hand.

      NOTICE:
      This inspection must be done quickly (within 10 seconds) to prevent damage to the heater fuel pump.
      OK:
      The pressure is applied to the hose.


NG
REPLACE HEATER FUEL PUMP
OK

REPLACE COMBUSTION HEATER ASSEMBLY