Toyota Avalon (XX50): MIL Circuit. Radiator Coolant Temperature Sensor Circuit Short to Ground (P00B111). Radiator Coolant Temperature Sensor Circuit Short to Battery or Open (P00B115)

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual / Engine / A25a-fxs Engine Control / Sfi System / MIL Circuit. Radiator Coolant Temperature Sensor Circuit Short to Ground (P00B111). Radiator Coolant Temperature Sensor Circuit Short to Battery or Open (P00B115)

MIL Circuit

DESCRIPTION

The Malfunction Indicator Lamp (MIL) is used to indicate vehicle malfunctions detected by the ECM.

The MIL operation can be checked visually. When the power switch is first turned to on (IG), the MIL should be illuminated and should then turn off after the engine is started. If the MIL remains illuminated or is not illuminated, conduct the following troubleshooting procedure using the Techstream.

WIRING DIAGRAM

PROCEDURE

1.	CHECK THAT MIL IS ILLUMINATED

(a) Perform troubleshooting in accordance with the table below.

MIL	Condition	Proceed to
Illuminates → Turns off	Power switch on (IG) → engine is started	A
Other than above	-	B

CHECK FOR INTERMITTENT PROBLEMS

2.	CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Check the communication between the Techstream and ECM.

HINT:

It can be checked using the "Engine" item of the Data List.

Result	Proceed to
Communication is possible	A
Communication is not possible	B

GO TO VC OUTPUT CIRCUIT

3.	CHECK WHETHER DTC OUTPUT RECURS

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Enter the following menus: System Select / Health Check.

(e) Check if any DTCs have been detected. Note down any DTCs.

Result	Proceed to
DTCs are not output	A
Any DTCs is output	B

HINT:

Check for detected DTCs output from other ECUs which relate to the MIL.

REPAIR CIRCUIT INDICATED BY OUTPUT

4.	PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Enter the following menus: Body Electrical / Combination Meter / Active Test / Check Engine Warning.

Body Electrical > Combination Meter > Active Test

Tester Display
Check Engine Warning

(e) Check the status of the MIL while performing the Active Test.

Result	Proceed to
Changes	A
Does not change	B

REPLACE ECM

REPLACE COMBINATION METER ASSEMBLY

Radiator Coolant Temperature Sensor Circuit Short to Ground (P00B111)

DESCRIPTION

The No. 2 engine coolant temperature sensor is installed to the radiator pipe between the engine and radiator and monitors the thermostat operation.

The structure of the thermistor used in the No. 2 engine coolant temperature sensor and its connection to the ECM are the same as those of the intake air temperature sensor.

Refer to DTC P011011.

Click here

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory	Note
P00B111	Radiator Coolant Temperature Sensor Circuit Short to Ground	The No. 2 engine coolant temperature sensor output voltage is less than 0.081 V for 3 seconds or more (1 trip detection logic).	Short in No. 2 engine coolant temperature sensor circuit No. 2 engine coolant temperature sensor ECM	Comes on	DTC stored	SAE Code: P00B3

MONITOR DESCRIPTION

The No. 2 engine coolant temperature sensor is used to monitor the engine coolant temperature. The No. 2 engine coolant temperature sensor has a thermistor with a resistance that varies according to the temperature of the engine coolant. When the engine coolant temperature is low, the resistance in the thermistor increases. When the temperature is high, the resistance decreases. These variations in resistance are reflected in the output voltage from the sensor. The ECM monitors the sensor voltage and uses this value to calculate the engine coolant temperature. If the No. 2 engine coolant temperature sensor output voltage deviates from the normal operating range, the ECM interprets this as a malfunction of the No. 2 engine coolant temperature sensor circuit, illuminates the MIL and stores a DTC.

Example:

If the No. 2 engine coolant temperature sensor output voltage is less than 0.081 V for 3 seconds or more, the ECM store this DTC.

MONITOR STRATEGY

Related DTCs	P00B3: No. 2 engine coolant temperature sensor range check (low voltage)
Required Sensors/Components (Main)	No. 2 engine coolant temperature sensor
Required Sensors/Components (Related)	-
Frequency of Operation	Continuous
Duration	3 seconds
MIL Operation	Immediate
Sequence of Operation	None

TYPICAL ENABLING CONDITIONS

Monitor runs whenever the following DTCs are not stored	None
Both of the following conditions are met	-
Auxiliary battery voltage	8 V or higher
Power switch	On (IG)

TYPICAL MALFUNCTION THRESHOLDS

No. 2 engine coolant temperature sensor voltage [Engine coolant temperature]

Less than 0.081 V [Higher than 163°C (325°F)]

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 Techstream to the DLC3.
Turn the power switch on (IG).
Turn the Techstream on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the power switch off and wait for at least 30 seconds.
Turn the power switch on (IG) [A].
Turn the Techstream on.
Wait 3 seconds or more [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: P00B111.

Check the DTC judgment result.

Techstream 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 is malfunctioning.
[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

CAUTION / NOTICE / HINT

NOTICE:

Vehicle Control History may be stored in the hybrid vehicle control ECU assembly 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.)

Click here
If any "Engine Malfunction" Vehicle Control History item has been stored in the hybrid vehicle control ECU assembly, 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 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.	INSPECT NO. 2 ENGINE COOLANT TEMPERATURE SENSOR

(a) Inspect the No. 2 engine coolant temperature sensor.

Click here

REPLACE NO. 2 ENGINE COOLANT TEMPERATURE SENSOR

2.	CHECK HARNESS AND CONNECTOR (NO. 2 ENGINE COOLANT TEMPERATURE SENSOR - ECM)

(a) Disconnect the No. 2 engine coolant temperature sensor connector.

(b) Disconnect the ECM connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
C42-2 or C55-129 (THTW) - Body ground and other terminals	Always	10 kΩ or higher

REPLACE ECM

REPAIR OR REPLACE HARNESS OR CONNECTOR

Radiator Coolant Temperature Sensor Circuit Short to Battery or Open (P00B115)

DESCRIPTION

Refer to DTC P00B111.

Click here

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory	Note
P00B115	Radiator Coolant Temperature Sensor Circuit Short to Battery or Open	The No. 2 engine coolant temperature sensor output voltage is higher than 4.91 V for 3 seconds or more (1 trip detection logic).	Open or short in No. 2 engine coolant temperature sensor circuit No. 2 engine coolant temperature sensor ECM	Comes on	DTC stored	SAE Code: P00B4

MONITOR DESCRIPTION

Example:

If the No. 2 engine coolant temperature sensor output voltage is higher than 4.91 V for 3 seconds or more, the ECM store this DTC.

MONITOR STRATEGY

Related DTCs	P00B4: No. 2 engine coolant temperature sensor range check (high voltage)
Required Sensors/Components (Main)	No. 2 engine coolant temperature sensor
Required Sensors/Components (Related)	-
Frequency of Operation	Continuous
Duration	3 seconds
MIL Operation	Immediate
Sequence of Operation	None

TYPICAL ENABLING CONDITIONS

Monitor runs whenever the following DTCs are not stored	None
Both of the following conditions are met	-
Auxiliary battery voltage	8 V or higher
Power switch	On (IG)

TYPICAL MALFUNCTION THRESHOLDS

No. 2 engine coolant temperature sensor voltage [Engine coolant temperature]

Higher than 4.91 V [Less than -57°C (-71°F)]

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 Techstream to the DLC3.
Turn the power switch on (IG).
Turn the Techstream on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the power switch off and wait for at least 30 seconds.
Turn the power switch on (IG) [A].
Turn the Techstream on.
Wait 3 seconds or more [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: P00B115.

Check the DTC judgment result.

Techstream 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 is malfunctioning.
[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 P00B111.

Click here

CAUTION / NOTICE / HINT

NOTICE:

Vehicle Control History may be stored in the hybrid vehicle control ECU assembly 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.)

Click here
If any "Engine Malfunction" Vehicle Control History item has been stored in the hybrid vehicle control ECU assembly, 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:

PROCEDURE

1.	INSPECT NO. 2 ENGINE COOLANT TEMPERATURE SENSOR

(a) Inspect the No. 2 engine coolant temperature sensor.

Click here

REPLACE NO. 2 ENGINE COOLANT TEMPERATURE SENSOR

2.	CHECK HARNESS AND CONNECTOR (NO. 2 ENGINE COOLANT TEMPERATURE SENSOR - ECM)

(a) Disconnect the No. 2 engine coolant temperature sensor connector.

(b) Disconnect the ECM connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
C42-2 - C55-129 (THTW)	Always	Below 1 Ω
C42-1 - C55-130 (ETHT)	Always	Below 1 Ω
C42-2 or C55-129 (THTW) - Other terminals	Always	10 kΩ or higher

REPLACE ECM

REPAIR OR REPLACE HARNESS OR CONNECTOR

How To Proceed With Troubleshooting. Ignition Circuit. Initialization

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