Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Lost Communication with Clock Device (Local-CAN) (B1326)

DESCRIPTION

After the combination meter assembly has started, the combination meter assembly attempts to detect the clock assembly by performing communication via local bus.

This DTC is stored when the clock assembly has been detected but communication between the combination meter assembly and clock assembly is interrupted.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Memory	Note
B1326	Lost Communication with Clock Device (Local-CAN)	Diagnosis Condition: The combination meter assembly has started Malfunction Status: After the clock assembly is detected, communication via local bus is interrupted Malfunction Time: 30 seconds or more	Radio receiver assembly Clock assembly Harness or connector Combination meter assembly	DTC stored	-

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

When replacing the combination meter assembly, always replace it with a new one. If a combination meter assembly which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.

PROCEDURE

1.	CHECK CLOCK ASSEMBLY

(a) Check the operation of the clock assembly.

Result	Proceed to
The clock assembly is operating correctly	A
The clock assembly is not operating correctly	B

B

GO TO STEP 4

A

2.	CHECK HARNESS AND CONNECTOR (POWER SOURCE - CLOCK ASSEMBLY)

(a) Disconnect the J79 clock assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
J79-1 (B) - Body ground	Engine switch off	11 to 14 V
J79-2 (ACC) - Body ground	Engine switch on (ACC)	11 to 14 V

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

3.	CHECK HARNESS AND CONNECTOR (CLOCK ASSEMBLY - BODY GROUND)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
J79-7 (E) - Body ground	Always	Below 1 Ω

OK

REPLACE CLOCK ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.	CONFIRM MODEL

(a) Choose the model to be inspected.

Result	Proceed to
w/o Navigation System	A
w/ Navigation System	B

B

GO TO STEP 7

A

5.	CHECK FOR DTC (AUDIO AND VISUAL SYSTEM)

(a) Check if audio and visual system DTCs are output.

Body Electrical > Navigation System > Trouble Codes

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

B

GO TO AUDIO AND VISUAL SYSTEM

A

6.	CHECK FOR DTC (AUDIO AND VISUAL SYSTEM)

(a) Disconnect the J79 clock assembly connector.

(b) Check if audio and visual system DTCs are output.

Body Electrical > Navigation System > Trouble Codes

HINT:

When the J79 connector of the clock assembly is disconnected and audio and visual system DTCs are output, if the radio receiver assembly detects the malfunction but the combination meter assembly does not, it can be suspected that the combination meter assembly is malfunctioning.

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

A

REPLACE RADIO RECEIVER ASSEMBLY

B

REPLACE COMBINATION METER ASSEMBLY

7.	CHECK FOR DTC (NAVIGATION SYSTEM)

(a) Check if navigation system DTCs are output.

Body Electrical > Navigation System > Trouble Codes

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

B

GO TO NAVIGATION SYSTEM

A

8.	CHECK FOR DTC (NAVIGATION SYSTEM)

(a) Disconnect the J79 clock assembly connector.

(b) Check if navigation system DTCs are output.

Body Electrical > Navigation System > Trouble Codes

HINT:

When the J79 connector of the clock assembly is disconnected and navigation system DTCs are output, if the radio receiver assembly detects the malfunction but the combination meter assembly does not, it can be suspected that the combination meter assembly is malfunctioning.

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

A

REPLACE RADIO RECEIVER ASSEMBLY

B

REPLACE COMBINATION METER ASSEMBLY