CAN COMMUNICATION SYSTEM, Diagnostic DTC:U0208

DTC Code	DTC Name
U0208	Lost Communication with "Seat Control Module A"

DESCRIPTION

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Note
U0208	Lost Communication with "Seat Control Module A"	No communication from the position control ECU and switch assembly LH continues. (for LHD) No communication from the position control ECU and switch assembly RH continues. (for RHD)	Position control ECU and switch assembly LH branch line or connector (for LHD) Power source circuit of position control ECU and switch assembly LH (for LHD) Position control ECU and switch assembly LH ground circuit (for LHD) Position control ECU and switch assembly LH (for LHD) Position control ECU and switch assembly RH branch line or connector (for RHD) Power source circuit of position control ECU and switch assembly RH (for RHD) Position control ECU and switch assembly RH ground circuit (for RHD) Position control ECU and switch assembly RH (for RHD)	Tech Tips The main body ECU (multiplex network body ECU) stores DTCs when it detects a communication stop or network communication error for ECUs connected to sub bus 1.

Tech Tips

This diagnostic procedure is for when DTC U0208 is output by the main body ECU (multiplex network body ECU) (GTS display: Main Body).

WIRING DIAGRAM

CAUTION / NOTICE / HINT

Note

Before measuring the resistance of the CAN bus, turn the engine switch off and leave the vehicle for 1 minute or more without operating the key or any switches, or opening or closing the doors. After that, disconnect the cable from the negative (-) battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.
After turning the engine switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

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Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output.

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After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.
DTC check procedure: Turn the engine switch on (IG) and wait for at least 20 seconds.
After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed.

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Inspect the fuses for circuits related to this system before performing the following procedure.

Tech Tips

Operating the engine switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.
Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.

PROCEDURE

RECONFIRM DTC OUTPUT

Body Electrical > Main Body > Trouble Codes

Reconfirm DTCs.

Tech Tips

If DTC U1002 is output from Main Body of the main body ECU (multiplex network body ECU), this indicates a sub bus 1 malfunction. Troubleshoot for DTC U1002 and check for malfunctions in sub bus 1.

Result

Result	Proceed to
DTC U1002 is not output from the main body ECU (multiplex network body ECU) (GTS display: Main Body)	A
DTC U1002 is output from the main body ECU (multiplex network body ECU) (GTS display: Main Body)	B

GO TO DIAGNOSTIC PROCEDURE INDICATED BY OUTPUT DTC Click here

CHECK VEHICLE TYPE

Check vehicle type.

Result

Result	Proceed to
for LHD	A
for RHD	B

CHECK FOR OPEN IN SUB BUS 1 LINES (POSITION CONTROL ECU AND SWITCH ASSEMBLY RH BRANCH LINE) Click here

CHECK FOR OPEN IN SUB BUS 1 LINES (POSITION CONTROL ECU AND SWITCH ASSEMBLY LH BRANCH LINE)

Disconnect the cable from the negative (-) battery terminal.
*a
Front view of wire harness connector

(to Position Control ECU and Switch Assembly LH)

Disconnect the c6 position control ECU and switch assembly LH connector.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
c6-8 (CANP) - c6-7 (CANN)	Cable disconnected from negative (-) battery terminal	54 to 69 Ω

Result

Result
OK
NG

REPAIR OR REPLACE CAN BRANCH LINES OR CONNECTOR (POSITION CONTROL ECU AND SWITCH ASSEMBLY LH)

CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

*a
Front view of wire harness connector

(to Position Control ECU and Switch Assembly LH)

Disconnect the c5 position control ECU and switch assembly LH connector.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
c5-2 (GND) - Body ground	Cable disconnected from negative (-) battery terminal	Below 1 Ω

Reconnect the cable to the negative (-) battery terminal.

*a	Front view of wire harness connector (to Position Control ECU and Switch Assembly LH)

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

Standard Voltage

Tester Connection	Condition	Specified Condition
c5-7 (+B) - Body ground	Always	11 to 14 V
c6-3 (IG) - Body ground	Engine switch on (IG)	11 to 14 V
c6-12 (SYSB) - Body ground	Always	11 to 14 V

Result

Result
OK
NG

REPLACE POSITION CONTROL ECU AND SWITCH ASSEMBLY LH Click here

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

CHECK FOR OPEN IN SUB BUS 1 LINES (POSITION CONTROL ECU AND SWITCH ASSEMBLY RH BRANCH LINE)

Disconnect the cable from the negative (-) battery terminal.
*a
Front view of wire harness connector

(to Position Control ECU and Switch Assembly RH)

Disconnect the b17 position control ECU and switch assembly RH connector.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
b17-8 (CANP) - b17-7 (CANN)	Cable disconnected from negative (-) battery terminal	54 to 69 Ω

Result

Result
OK
NG

REPAIR OR REPLACE CAN BRANCH LINES OR CONNECTOR (POSITION CONTROL ECU AND SWITCH ASSEMBLY RH)

CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

*a
Front view of wire harness connector

(to Position Control ECU and Switch Assembly RH)

Disconnect the b16 position control ECU and switch assembly RH connector.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
b16-2 (GND) - Body ground	Cable disconnected from negative (-) battery terminal	Below 1 Ω

Reconnect the cable to the negative (-) battery terminal.

*a	Front view of wire harness connector (to Position Control ECU and Switch Assembly RH)

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

Standard Voltage

Tester Connection	Condition	Specified Condition
b16-7 (+B) - Body ground	Always	11 to 14 V
b17-3 (IG) - Body ground	Engine switch on (IG)	11 to 14 V
b17-12 (SYSB) - Body ground	Always	11 to 14 V

Result

Result
OK
NG

REPLACE POSITION CONTROL ECU AND SWITCH ASSEMBLY RH Click here

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)