SFI SYSTEM(w/o Canister Pump Module), Diagnostic DTC:P148F00

DTC Code	DTC Name
P148F00	Engine Coolant Pump Over Revolution

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.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory	Note
P148F00	Engine Coolant Pump Over Revolution	When both of the following conditions are met for 5 seconds or more (1 trip detection logic): Engine water pump assembly duty cycle is 85% or higher. Actual engine water pump assembly speed exceeds the target for a certain amount of time.	Lack of engine coolant Engine coolant leak Engine water pump assembly	Does not come on	DTC stored	SAE Code: P148F

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

Note

P148F00

Engine Coolant Pump Over Revolution

When both of the following conditions are met for 5 seconds or more (1 trip detection logic):

Engine water pump assembly duty cycle is 85% or higher.
Actual engine water pump assembly speed exceeds the target for a certain amount of time.

Lack of engine coolant
Engine coolant leak
Engine water pump assembly

Does not come on

DTC stored

SAE Code: P148F

MONITOR DESCRIPTION

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.)

CAUTION / NOTICE / HINT

Tech Tips

DTC P148F00 may be stored if the engine has continuously run with insufficient engine coolant. If the engine coolant is sufficient and DTC P148F00 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 GTS. 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

CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P148F00)

Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Enter the following menus: Powertrain / Engine / Trouble Codes.

Read the DTCs.

Powertrain > Engine > Trouble Codes

Result

Result	Proceed to
DTC P148F00 is output	A
DTC P148F00 and other DTCs are output	B

Tech Tips

If any DTCs other than P148F00 are output, troubleshoot those DTCs first.

GO TO DTC CHART Click here

CHECK RESERVE SEALED TANK WITHOUT CAP (ENGINE COOLANT LEVEL)

Check that the engine coolant level is between the FULL and LOW lines.

Result

Result	Proceed to
Engine coolant level is below the LOW line	A
Engine coolant level is above the LOW line	B

GO TO STEP 6 Click here

CHECK FOR ENGINE COOLANT LEAKS

Check the areas around the engine and heater for engine coolant leaks.

Tech Tips

If the engine oil is cloudy during the engine oil level gauge check, it means that engine coolant has entered the engine lubrication system.

OK
No leaks.

Result

Proceed to
OK
NG

REPAIR OR REPLACE MALFUNCTIONING PARTS, COMPONENT AND AREA Click here

ADD ENGINE COOLANT

Fill the reservoir tank up to the FULL line with engine coolant.

Note

Make sure not to add engine coolant when the engine is hot.

Result

Proceed to
NEXT

GO TO STEP 6 Click here

REPAIR OR REPLACE MALFUNCTIONING PARTS, COMPONENT AND AREA

Repair any engine coolant leaks.

Tech Tips

Add engine coolant and perform air bleeding after repair.

Click here

Result

Proceed to
NEXT

CLEAR DTC

Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Clear the DTCs.

Powertrain > Engine > Clear DTCs

Turn the power switch off and wait for at least 30 seconds.

Result

Proceed to
NEXT

INSPECT ENGINE WATER PUMP ASSEMBLY

Tech Tips

Perform this inspection indoors.

Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Put the engine in Inspection Mode (Maintenance Mode).

Click here

Powertrain > Hybrid Control > Utility

Tester Display

Inspection Mode
Start the engine.

Tester Display
Inspection Mode

Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature and Electric Water Pump Speed.

Tech Tips

Display the Data List items on the graph view.

Powertrain > Engine > Data List

Tester Display
Coolant Temperature
Electric Water Pump Speed

Idle the engine for about 20 minutes and check Coolant Temperature, Electric Water Pump Speed using the GTS, and check the cooling fans.

Result

Proceed to

Either of the following conditions is met:

The engine coolant temperature becomes 95°C (203°F) or higher and the engine water pump assembly performs intermittent operation (5 seconds pause after 25 seconds operation).
The engine water pump assembly does not start operating even after the engine coolant temperature becomes 95°C (203°F) or higher.*1, *2

The cooling fans start operating after the engine coolant temperature becomes 95°C (203°F) or less and a decrease in the engine coolant temperature is observed.*3

Tech Tips

*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 operated excessively due to insufficient coolant etc., the Electric Water Pump Speed will exceed 5300 rpm. Enter the following menus to check the voltage of the ECM: Powertrain / Engine / Data List / Battery Voltage.
*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).

END

REPLACE ENGINE WATER PUMP ASSEMBLY

Replace the engine water pump assembly.

Click here

Result

Proceed to
NEXT

ADD ENGINE COOLANT

Fill the reservoir tank up to the FULL line with engine coolant.

Note

Make sure not to add engine coolant when the engine is hot.

Result

Proceed to
NEXT

CLEAR DTC

Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Clear the DTCs.

Powertrain > Engine > Clear DTCs

Turn the power switch off and wait for at least 30 seconds.

Result

Proceed to
NEXT

CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

Tech Tips

Perform this inspection indoors.

Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Put the engine in Inspection Mode (Maintenance Mode).

Click here

Powertrain > Hybrid Control > Utility

Tester Display

Inspection Mode
Start the engine.

Tester Display
Inspection Mode

Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature and Electric Water Pump Speed.

Powertrain > Engine > Data List

Tester Display
Coolant Temperature
Electric Water Pump Speed

Idle the engine for about 20 minutes and check Coolant Temperature, Electric Water Pump Speed using the GTS, and check the cooling fans.

OK
The cooling fans start operating after the engine coolant temperature becomes 95°C (203°F) or less and a decrease in the engine coolant temperature is observed.

Result

Proceed to
NEXT

END