COMBUSTION TYPE POWER HEATER SYSTEM Power Heater Fuel Pump Circuit
| DTC Code | DTC Name |
|---|---|
| Power Heater Fuel Pump Circuit |
DESCRIPTION
When the heater switch assembly is turned on, the heater assembly sends a drive signal to the heater pump assembly. The heater assembly then receives the fuel necessary for combustion and starts operating.
WIRING DIAGRAM
PROCEDURE
CHECK HARNESS AND CONNECTOR (HEATER ASSEMBLY - HEATER PUMP ASSEMBLY)
Disconnect the A42 heater assembly connector.
Disconnect the A99 heater pump assembly connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection
Condition
Specified Condition
A42-2 (L) - A99-1
Always
Below 1 Ω
A42-2 (L) - Body ground
Always
10 kΩ or higher
Result
Proceed to
OK
NG
NG REPAIR OR REPLACE HARNESS OR CONNECTOR
CHECK HARNESS AND CONNECTOR (HEATER PUMP ASSEMBLY - BODY GROUND)
Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection
Condition
Specified Condition
A99-2 - Body ground
Always
Below 1 Ω
Result
Proceed to
OK
NG
NG REPAIR OR REPLACE HARNESS OR CONNECTOR
INSPECT HEATER PUMP ASSEMBLY
-
*a
Component without harness connected
(Heater Pump Assembly)
Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection
Condition
Specified Condition
1 - 2
Always
9 to 12 Ω
Inspect heater pump assembly operation.
Connect a positive (+) lead from the battery to terminal 1 and a negative (-) lead to terminal 2, and check the pressure of the hose by hand.
Note:This inspection must be done quickly (within 10 seconds) to prevent damage to the heater pump assembly.
OK
Pressure is applied to the hose.
Result
Proceed to
OK
NG
-
INSPECT HEATER ASSEMBLY
Reconnect the A42 heater assembly connector.
Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection
Condition
Specified Condition
A99-1 - Body ground
Engine running
Heater switch assembly: On
11 to 14 V
A99-1 - Body ground
Engine running
Heater switch assembly: Off
Below 1 V
Result
Proceed to
OK
NG