INSPECT TANK HEATER (UREA PUMP)
CHECK HARNESS AND CONNECTOR (TANK HEATER (UREA PUMP) - UREA PUMP CONTROL ECU))
REPAIR OR REPLACE HARNESS AND CONNECTOR
DTC P202B Reductant Tank Heater Control Circuit Low |
DTC P202C Reductant Tank Heater Control Circuit High |
DESCRIPTION
An electric heater is provided inside the urea tank and urea pipe, as urea solution freezes at -11°C (12.2°F) or lower.The heater thaws frozen urea solution and prevents further freezing, allowing the urea SCR system to be started even in cold environments.
The tank heater turns ON and OFF according to the value of the temperature sensor. The heater for the urea tube with heater assembly turns ON and OFF according to the value of the ambient temperature sensor.
| DTC Detection Drive Pattern | DTC Detection Condition | Trouble Area |
| Reductant Tank Heater (Active Test) | When the tank heater is operating, an open or short circuit occurs in the tank heater for 3 seconds or more. (1 trip detection logic) |
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| DTC Detection Drive Pattern | DTC Detection Condition | Trouble Area |
| Reductant Tank Heater (Active Test) | When the tank heater is operating, an open or short circuit occurs in the tank heater for 3 seconds or more. (1 trip detection logic) |
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| DTC No. | Data List |
| P202B P202C | Reductant Tank Heater |
WIRING DIAGRAM
INSPECTION PROCEDURE
- HINT:
- Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.
| 1.INSPECT TANK HEATER (UREA PUMP) |
Inspect the tank heater (urea pump) (LandCruiser RM000005UKY000X_01_0001.html).
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| OK | |
| 2.CHECK HARNESS AND CONNECTOR (TANK HEATER (UREA PUMP) - UREA PUMP CONTROL ECU)) |
Disconnect the tank heater (urea pump) connector.
Disconnect the urea pump control ECU connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition s2-9 (TH+) - s3-21 (HTT) Always Below 1 Ω s2-11 (TH-) - s3-31 (EHTT) Always Below 1 Ω s2-9 (TH+) or s3-21 (HTT) - Body ground and other terminals Always 10 kΩ or higher s2-11 (TH-) or s3-31 (EHTT) - Body ground and other terminals Always 10 kΩ or higher
| *a | Front view of wire harness connector (to Tank Heater (urea pump)) | *b | Front view of wire harness connector (to Urea Pump Control ECU) |
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| OK | |
| 3.CLEAR DTC |
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Clear the DTCs (LandCruiser RM000000PDK1E5X.html).
Turn the engine switch off for 30 seconds or more.
| NEXT | |
| 4.CHECK DTC OUTPUT |
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Reductant Tank Heater .
Perform the Active Test.
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
Read the DTCs.
- Result:
Result Proceed to DTC P202B or P202C is output A DTCs is not output B
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| A | |
| 5.REPLACE UREA PUMP CONTROL ECU |
Replace the urea pump control ECU (LandCruiser RM000005UL6000X.html).
| NEXT | |
| 6.CLEAR DTC |
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Clear the DTCs (LandCruiser RM000000PDK1E5X.html).
Turn the engine switch off for 30 seconds or more.
| NEXT | |
| 7.CHECK DTC OUTPUT |
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Reductant Tank Heater.
Perform the Active Test.
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
Confirm that the DTC is not output again.
| NEXT | ||
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| 8.REPAIR OR REPLACE HARNESS AND CONNECTOR |
Repair or replace the harness or connector.
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| 9.REPLACE UREA PUMP |
Replace the urea pump (LandCruiser RM000005UL0000X.html).
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