DESCRIPTION
When the power heater switch is turned on, the heater pump assembly receives a drive voltage from the heater assembly (ECU). The heater pump assembly provides the heater assembly with fuel necessary for combustion, allowing the heater assembly to operate.
INSPECTION PROCEDURE
PROCEDURE
- Click here
CHECK HARNESS AND CONNECTOR (HEATER ASSEMBLY - HEATER PUMP ASSEMBLY AND BODY GROUND)
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Disconnect the A41 heater connector.
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Disconnect the A42 pump connector.
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Measure the resistance according to the value(s) in the table below.
Standard Resistance Tester Connection Condition Specified Condition A41-2 (L) - A42-1 (B2) Always Below 1 Ω A42-2 (E2) - Body ground Always Below 1 Ω A41-2 (L) - Body ground Always 10 kΩ or higher Table 1. Text in Illustration *1 Front view of wire harness connector
(to Heater Assembly)
*2 Front view of wire harness connector
(to Heater Pump Assembly)
- OKClick here
- NGClick here
-
- Click here
INSPECT HEATER PUMP ASSEMBLY
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Remove the heater pump assembly with the fuel hose still connected (Click here).
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Measure the resistance according to the value(s) in the table below.
Standard Resistance Tester Connection Condition Specified Condition 1 (B2) - 2 (E2) Always 9 to 12 Ω -
Apply battery voltage to the heater pump assembly and check the pressure of the hose by hand.
OK Measurement Condition Specified Condition Battery positive (+) → Terminal 1
Battery negative (-) → Terminal 2
Pressure is applied to the hose Note:
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This inspection must be done quickly (within 10 seconds) to prevent damage to the heater pump assembly.
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Always switch the voltage on and off on the battery side, not the heater pump assembly side.
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Keep the heater pump assembly as far away from the battery as possible.
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- OKClick here
- NGClick here
-
- Click here
REPAIR OR REPLACE HARNESS OR CONNECTOR
- Click here
REPLACE HEATER PUMP ASSEMBLYClick here
- Click here
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLEClick here