- Coolant Temperature
- Electric Water Pump Target Speed
- Electric Water Pump Speed
| Last Modified: 05-13-2024 | 6.11:8.1.0 | Doc ID: RM1000000026JSN |
| Model Year Start: 2023 | Model: Corolla | Prod Date Range: [09/2022 - ] |
| Title: 2ZR-FXE (ENGINE CONTROL): SFI SYSTEM: P26CA14; Engine Coolant Pump Circuit Short to Ground or Open; 2023 - 2025 MY Corolla Corolla HV [09/2022 - ] | ||
|
DTC |
P26CA14 |
Engine Coolant Pump Circuit Short to Ground or Open |
DESCRIPTION
Refer to DTC P26CA12.
Click here
![2023 - 2025 MY Corolla Corolla HV [09/2022 - ]; 2ZR-FXE (ENGINE CONTROL): SFI SYSTEM: P26CA12; Engine Coolant Pump Circuit Short to Battery+](/t3Portal/stylegraphics/info.gif)
|
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
MIL |
Memory |
Note |
|---|---|---|---|---|---|---|
|
P26CA14 |
Engine Coolant Pump Circuit Short to Ground or Open |
The operation duty ratio (WPO) of the monitoring engine water pump assembly becomes a certain amount or less when engine water pump assembly operation command is output (1 trip detection logic). |
|
Comes on |
DTC stored |
|
Related Data List
|
DTC No. |
Data List |
|---|---|
|
P26CA14 |
|
MONITOR DESCRIPTION
The ECM outputs an operation duty signal (WPO) to steplessly control the speed of the engine water pump assembly. The ECM outputs an operation duty signal (WPO) to the engine water pump assembly and monitors the actual duty signal (WPO) being output. When the operation duty signal (WPO) is being output to the engine water pump assembly and the actual operation duty signal (WPO) is a certain value or less, the ECM detects a malfunction and stores a DTC.
MONITOR STRATEGY
|
Related DTCs |
P26CC: Engine water pump circuit range check (Low voltage) |
|
Required Sensors/Components (Main) |
Engine water pump assembly |
|
Required Sensors/Components (Related) |
- |
|
Frequency of Operation |
Continuous |
|
Duration |
3 seconds |
|
MIL Operation |
Immediate |
|
Sequence of Operation |
None |
TYPICAL ENABLING CONDITIONS
|
All of the following conditions are met |
- |
|
Auxiliary battery voltage |
8 V or higher |
|
Ignition switch |
On |
|
Time after ignition switch off to ON |
0.5 seconds or more |
|
Output duty cycle |
30 to 85% |
|
Engine water pump circuit pulse input fail (P26CA) |
Not detected |
TYPICAL MALFUNCTION THRESHOLDS
|
Both of the following conditions are met |
- |
|
Engine water pump assembly output terminal voltage level |
Low |
|
Engine water pump assembly output signal |
No signal |
CONFIRMATION DRIVING PATTERN
HINT:
-
After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.
Click here
-
When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.
Click here
- Connect the GTS to the DLC3.
- Turn the ignition switch to ON.
- Turn the GTS on.
- Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
- Turn the ignition switch off and wait for at least 30 seconds.
- Turn the ignition switch to ON [A].
- Turn the GTS on.
-
Put the engine in Inspection Mode (Maintenance Mode).
Click here
- Start the engine and maintain the engine speed at 2500 rpm or more for at least 40 seconds [B].
- Enter the following menus: Powertrain / Engine / Trouble Codes [C].
-
Read the pending DTCs.
HINT:
- If a pending DTC is output, the system is malfunctioning.
- If a pending DTC is not output, perform the following procedure.
- Enter the following menus: Powertrain / Engine / Utility / All Readiness.
- Input the DTC: P26CA14.
-
Check the DTC judgment result.
GTS Display
Description
NORMAL
- DTC judgment completed
- System normal
ABNORMAL
- DTC judgment completed
- System abnormal
INCOMPLETE
- DTC judgment not completed
- Perform driving pattern after confirming DTC enabling conditions
HINT:
- If the judgment result is NORMAL, the system is normal.
- If the judgment result is ABNORMAL, the system has a malfunction.
- If the judgment result is INCOMPLETE, perform steps [B] through [C] again.
-
[A] to [C]: Normal judgment procedure.
The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
- When clearing the permanent DTCs, do not disconnect the cable from the auxiliary battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.
WIRING DIAGRAM
Refer to DTC P26CA12.
Click here
CAUTION / NOTICE / HINT
NOTICE:
-
Vehicle Control History may be stored in the hybrid vehicle control ECU if the engine is malfunctioning. Certain vehicle condition information is recorded when Vehicle Control History is stored. Reading the vehicle conditions recorded in both the freeze frame data and Vehicle Control History can be useful for troubleshooting.
Click here
(Select Powertrain in Health Check and then check the time stamp data.)
-
If any "Engine Malfunction" Vehicle Control History item has been stored in the hybrid vehicle control ECU, make sure to clear it. However, as all Vehicle Control History items are cleared simultaneously, if any Vehicle Control History items other than "Engine Malfunction" are stored, make sure to perform any troubleshooting for them before clearing Vehicle Control History.
Click here
HINT:
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
|
1. |
INSPECT ECM (INTERNAL CIRCUIT) |
(a) Disconnect the engine water pump assembly (water inlet housing) connector.
(b) Perform the Active Test using the GTS.
Powertrain > Engine > Active Test
|
Tester Display |
|---|
|
Activate the Electric Water Pump |
(c) Measure the resistance according to the value(s) in the table below.
Standard:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
C126-3 (SWP) - Body ground |
During Active Test |
Resistance fluctuates* |
HINT:
- *: Using the Active Test, duty control of the transistors in the ECM will be performed. Due to the duty control, resistance of the SWP terminal will be unstable during the Active Test. If the resistance fluctuates while performing the Active Test, it can be determined that the transistor is operating. If the transistor does not operate during the Active Test, the ECM may be malfunctioning.
| OK |
|
|
|
2. |
CHECK HARNESS AND CONNECTOR (ENGINE WATER PUMP ASSEMBLY (WATER INLET HOUSING) - ECM) |
(a) Disconnect the engine water pump assembly (water inlet housing) connector.
(b) Disconnect the ECM connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
C126-3 (SWP) - C147-71 (WPO) |
Always |
Below 1 Ω |
|
C126-3 (SWP) or C147-71 (WPO) - Body ground |
Always |
10 kΩ or higher |
| OK |
|
REPLACE ECM
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|