- 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
| Last Modified: 05-13-2024 | 6.11:8.1.0 | Doc ID: RM100000001GJ73 |
| Model Year Start: 2020 | Model: Corolla | Prod Date Range: [01/2019 - 04/2020] |
| Title: 2ZR-FXE (ENGINE CONTROL): SFI SYSTEM: P148F00; Engine Coolant Pump Over Revolution; 2020 MY Corolla Corolla HV [01/2019 - 04/2020] | ||
|
DTC |
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):
|
|
Does not come on |
DTC stored |
|
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
HINT:
- 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 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 P148F00) |
(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 / Trouble Codes.
(e) Read the DTCs.
Powertrain > Engine > Trouble Codes
|
Result |
Proceed to |
|---|---|
|
DTC P148F00 is output |
A |
|
DTC P148F00 and other DTCs are output |
B |
HINT:
If any DTCs other than P148F00 are output, troubleshoot those DTCs first.
| B |
|
|
|
2. |
CHECK RESERVE SEALED TANK WITHOUT CAP (ENGINE COOLANT LEVEL) |
(a) Check that the engine coolant level is between the FULL and LOW lines.
|
Result |
Proceed to |
|---|---|
|
Engine coolant level is below the LOW line |
A |
|
Engine coolant level is above the LOW line |
B |
| B |
|
|
|
3. |
CHECK FOR ENGINE COOLANT LEAKS |
(a) Check the areas around the engine and heater for engine coolant 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.
OK:
No leaks.
| NG |
|
|
|
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 |
|
|
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.
|
|
6. |
CLEAR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs.
Powertrain > Engine > Clear DTCs
(e) Turn the power switch off and wait for at least 30 seconds.
|
|
7. |
INSPECT ENGINE WATER PUMP ASSEMBLY |
HINT:
Perform this inspection indoors.
(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).
Click here
![2019 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2018 - ]; INTRODUCTION: REPAIR INSTRUCTION: INSPECTION MODE PROCEDURE](/t3Portal/stylegraphics/info.gif)
Powertrain > Hybrid Control > Utility
|
Tester Display |
|---|
|
Inspection Mode |
(e) Start the engine.
(f) Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature and Electric Water Pump Speed.
HINT:
Display the Data List items on the graph view.
Powertrain > Engine > Data List
|
Tester Display |
|---|
|
Coolant Temperature |
|
Electric Water Pump Speed |
(g) Idle the engine for about 20 minutes and check Coolant Temperature, Electric Water Pump Speed using the Techstream, and check the cooling fans.
|
Result |
Proceed to |
|---|---|
|
Either of the following conditions is met: |
A |
|
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 |
B |
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 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).
| B |
|
END |
|
|
8. |
REPLACE ENGINE WATER PUMP ASSEMBLY |
(a) Replace the engine water pump assembly.
Click here
|
|
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.
|
|
10. |
CLEAR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs.
Powertrain > Engine > Clear DTCs
(e) Turn the power switch off and wait for at least 30 seconds.
|
|
11. |
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED |
HINT:
Perform this inspection indoors.
(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).
Click here
Powertrain > Hybrid Control > Utility
|
Tester Display |
|---|
|
Inspection Mode |
(e) Start the engine.
(f) 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 |
(g) Idle the engine for about 20 minutes and check Coolant Temperature, Electric Water Pump Speed using the Techstream, 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.
| NEXT |
|
END |
|
|