DTC B1247: Tire Pressure Monitor Receiver Communication Stop [06/2018 - ]: Procedure

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INSPECT TIRE PRESSURE WARNING ECU AND RECEIVER (OUTPUT WAVEFORM)

Using an oscilloscope, check the waveform.

NOTE:

With the connector connected, check from the backside of the connector.

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*a	Component with harness connected (Tire Pressure Warning ECU and Receiver)
*b	GND

Tester Connection	Tool Setting Range	Condition	Specified Condition
N8-4 (RDA) - Body ground	5 V/DIV.5 ms./DIV.	Power switch on (IG)	Waveform generation

Result

Result	Proceed to
Waveform is as shown in the illustration. (Waveform alternates between 10.5 V or higher and 0.5 V or less)	A
Waveform does not change from 10.5 V or higher	B
Waveform does not change from 0.5 V or less	C

Result:

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to REMOVAL [06/2018 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]

Result:

REPLACE TIRE PRESSURE WARNING ECU AND RECEIVER. Refer to REMOVAL [06/2018 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]

Result:

See step 2

CHECK TERMINAL VOLTAGE (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) OUTPUT)

Disconnect the N8 tire pressure warning ECU and receiver connector.

Measure the voltage according to the value(s) in the table below.

Standard Voltage

Tester Connection	Condition	Specified Condition
N8-4 (RDA) - Body ground	Power switch on (IG)	10.5 V or higher

Result

Proceed to
OK
NG

Result:

REPLACE TIRE PRESSURE WARNING ECU AND RECEIVER. Refer to REMOVAL [06/2018 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]

Result:

See step 3

CHECK HARNESS AND CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) - TIRE PRESSURE WARNING ECU AND RECEIVER)

Turn the power switch off.
Disconnect the G38 main body ECU (multiplex network body ECU) connector.

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
G38-10 (RDA) - N8-4 (RDA)	Always	Below 1 Ω
G38-10 (RDA) or N8-4 (RDA) - Body ground	Always	10 kΩ or higher

Result

Proceed to
OK
NG

Result:

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to REMOVAL [06/2018 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]

Result:

REPAIR OR REPLACE HARNESS OR CONNECTOR