P148F
2AR-FXE ENGINE CONTROL: SFI SYSTEM: P148F: Engine Coolant Pump Over Revolution
P148F - Engine Coolant Pump Over Revolution
MONITOR DESCRIPTION
The ECM controls the engine water pump assembly by calculating the necessary amount of coolant flow based on engine coolant temperature, engine speed and vehicle speed information. The speed of the engine water pump assembly is controlled steplessly using a duty cycle signal sent from the ECM. This optimal control enhances warm-up performance and reduces cooling losses, thus reducing the specific fuel consumption of the engine. The ECM monitors the speed of the engine water pump assembly and stores a DTC when it determines that the engine water pump assembly rotates excessively based on the fact that the actual speed is higher than the target for a certain amount of time. (However, the MIL will not illuminate.)
HINT
The 7th bar of the water temperature receiver gauge blinks when the coolant temperature becomes 118°C (244°F) or higher.
INSPECTION PROCEDURE
HINT
* DTC P148F may be stored if the engine has continuously run with insufficient engine coolant. If the engine coolant is sufficient and DTC P148F recur when the vehicle is brought to the workshop, confirm whether engine coolant was added after the vehicle had been driven with insufficient engine coolant.
* Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.
PROCEDURE
1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P148F)
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
(e) Read the DTCs.
Result
HINT
If any DTCs other than P148F are output, troubleshoot those DTCs first.
B -- GO TO DTC CHART SFI System
A -- Continue to next step.
2. CHECK RADIATOR RESERVOIR TANK ASSEMBLY (ENGINE COOLANT LEVEL)
(a) Check that the engine coolant level is between the FULL and LOW lines Testing and Inspection.
Result
B -- CLEAR DTC (DTC P148F)
A -- Continue to next step.
3. CHECK FOR ENGINE COOLANT LEAKS
(a) Check the areas around the engine and heater for engine coolant leaks Testing and Inspection.
OK:
No leaks.
HINT
If the engine oil is cloudy during the engine oil level gauge check, it means that engine coolant has entered the engine lubrication system.
NG -- REPAIR OR REPLACE MALFUNCTIONING PARTS, COMPONENT AND AREA
OK -- Continue to next step.
4. ADD ENGINE COOLANT
(a) Fill the reservoir tank up to the FULL line with engine coolant.
NOTICE:
Make sure not to add engine coolant when the engine is hot.
NEXT -- CLEAR DTC (DTC P148F)
5. REPAIR OR REPLACE MALFUNCTIONING PARTS, COMPONENT AND AREA
(a) Repair any engine coolant leaks.
HINT
Add engine coolant and perform air bleeding after repair Coolant (for Engine).
NEXT -- Continue to next step.
6. CLEAR DTC (DTC P148F)
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
NEXT -- Continue to next step.
7. INSPECT ENGINE WATER PUMP ASSEMBLY
HINT
Perform repair indoors or in a workshop.
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Put the engine in inspection mode (maintenance mode) Component Tests and General Diagnostics.
(e) Start the engine.
(f) Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / Coolant Temp and Elec Water Pump Spd.
HINT
Display the Data List diagram.
(g) Idle the engine for about 20 minutes and check Coolant Temp, Elec Water Pump Spd using the Techstream, and check the cooling fans.
Result
HINT
* *1: Be careful when the cooling fans do not start operating even after the engine coolant temperature becomes 95°C (203°F) or higher because the engine coolant temperature increases rapidly. (Make sure to stop the engine if the engine coolant temperature becomes 105°C (221°F) or higher.)
* *2: If the ECM voltage is 14 V or higher and the engine water pump assembly is run excessively due to insufficient coolant etc., the water pump motor speed will exceed 5000 rpm. Enter the following menus to check the voltage of the ECM: Powertrain / Engine and ECT / Data List / Primary / Battery Voltage Data List / Active List.
* *3: When the engine is warmed up, the cooling fans operate and the engine coolant temperature will decrease. After the cooling fans begin operating, the engine coolant temperature will stabilize between 88 to 95°C (190 to 203°F).
B -- END
A -- Continue to next step.
8. REPLACE ENGINE WATER PUMP ASSEMBLY
(a) Replace the engine water pump assembly Removal.
NEXT -- Continue to next step.
9. ADD ENGINE COOLANT
(a) Fill the reservoir tank up to the FULL line with engine coolant.
NOTICE:
Make sure not to add engine coolant when the engine is hot.
NEXT -- Continue to next step.
10. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
HINT
Perform repair indoors or in a workshop.
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(e) Put the engine in inspection mode (maintenance mode) Component Tests and General Diagnostics.
(f) Start the engine.
(g) Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / Coolant Temp and Elec Water Pump Spd.
(h) Idle the engine for about 20 minutes and check Coolant Temp, Elec Water Pump Spd using the Techstream, and check the cooling fans.
Result:
The cooling fans start operating after the engine coolant temperature becomes 95°C (203°F) or less and decrease in the engine coolant temperature is observed.
NEXT -- END