RM38N0EC _58 Vehicle Interior _111839 SEAT _0505696 SEAT HEATER SYSTEM C

SEAT SEAT HEATER SYSTEM B14B587 Lost Communication with Front Seat Temperature Adjustment Switch LIN Missing Message

DESCRIPTION

The front seat heater switch (refreshing seat switch) communicates with the air conditioning amplifier assembly via LIN communication.

If the LIN communication system is malfunctioning, the air conditioning amplifier assembly will not operate even if the front seat heater switch (refreshing seat switch) is operated.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	DTC Output from	Priority
B14B587	Lost Communication with Front Seat Temperature Adjustment Switch LIN Missing Message	A communication error or interruption between the refreshing seat switch and air conditioning amplifier assembly continues for 10 seconds or more.	· Front seat heater switch (Refreshing seat switch) · Air conditioning amplifier assembly · Wire harness or connector · ECU-IGP NO. 3 fuse	Air Conditioner	A

WIRING DIAGRAM

1.281,0.792 1.896,0.99 0.615,0.198 10 false LIN1 1.667,0.625 2.281,0.823 0.615,0.198 10 false 7 2.698,0.625 3.313,0.823 0.615,0.198 10 false 8 0.281,1.635 0.896,1.833 0.615,0.198 10 false E44 0.271,1.781 1.792,2.333 1.521,0.552 10 false Air Conditioning Amplifier Assembly 2.74,1.646 3.354,1.844 0.615,0.198 10 false L9 2.75,1.802 4.365,2.229 1.615,0.427 10 false Front Seat Heater Switch (Refreshing Seat Switch) 3.885,1.208 4.5,1.406 0.615,0.198 10 false E 4.104,1.083 4.719,1.281 0.615,0.198 10 false 7 3.844,0.396 4.458,0.594 0.615,0.198 10 false IG 4.104,0.271 4.719,0.469 0.615,0.198 10 false 9 4.438,0.552 5.563,0.75 1.125,0.198 10 false ECU-IGP NO. 3 5.688,0.396 7.125,0.625 1.438,0.229 10 false from IGP Relay 0.792,2.458 2.573,2.74 1.781,0.281 10 false : LIN Communication Line 2.885,0.771 3.5,0.969 0.615,0.198 10 false SLIN

CAUTION / NOTICE / HINT

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

PROCEDURE

1.CLEAR DTC

Clear the DTCs.

Body Electrical > Air Conditioner > Clear DTCs: 50002 450

Result:

Proceed to
NEXT

2.CHECK FOR DTC

Check for DTCs.

Body Electrical > Air Conditioner > Trouble Codes: 50001 450

Result:

Result	Proceed to
B14B587 is not output	A
B14B587 is output	B

USE SIMULATION METHOD TO CHECK

Click hereGeneral>INTRODUCTION>HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS>HOW TO PROCEED WITH TROUBLESHOOTING202111,999999,_V1,_111779,_0504974,RM100000001ZKRQ,

3.CHECK HARNESS AND CONNECTOR (IG POWER SUPPLY - FRONT SEAT HEATER SWITCH (REFRESHING SEAT SWITCH) - BODY GROUND)

Pre-procedure1

Disconnect the L9 front seat heater switch (refreshing seat switch) connector.

Procedure1

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
Click Location & Routing(L9)Location & Routingewd_type=routing;type=c;code=L9 Click Connector(L9)Instrument Panel>No. 2 Floor Wire>Refreshing Seat Switchewd_type=component;type=c;code=L9;pinno=9
L9-9 (IG) - Body ground	Ignition switch ON	11 to 14 V
L9-9 (IG) - Body ground	Ignition switch off	Below 1 V

Tester Connection

Condition

Specified Condition

Click Location & Routing(L9)Location & Routingewd_type=routing;type=c;code=L9

Click Connector(L9)Instrument Panel>No. 2 Floor Wire>Refreshing Seat Switchewd_type=component;type=c;code=L9;pinno=9

L9-9 (IG) - Body ground

Ignition switch ON

11 to 14 V

L9-9 (IG) - Body ground

Ignition switch off

Below 1 V

Standard Resistance:

Tester Connection	Condition	Specified Condition
Click Location & Routing(L9)Location & Routingewd_type=routing;type=c;code=L9 Click Connector(L9)Instrument Panel>No. 2 Floor Wire>Refreshing Seat Switchewd_type=component;type=c;code=L9;pinno=7
L9-7 (E) - Body ground	Always	Below 1 Ω

Tester Connection

Condition

Specified Condition

Click Location & Routing(L9)Location & Routingewd_type=routing;type=c;code=L9

Click Connector(L9)Instrument Panel>No. 2 Floor Wire>Refreshing Seat Switchewd_type=component;type=c;code=L9;pinno=7

L9-7 (E) - Body ground

Always

Below 1 Ω

Result:

Proceed to
OK
NG

Post-procedure1

None

4.CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - FRONT SEAT HEATER SWITCH (REFRESHING SEAT SWITCH))

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - FRONT SEAT HEATER SWITCH (REFRESHING SEAT SWITCH))

Pre-procedure1

Disconnect the E44 air conditioning amplifier assembly connector.

Procedure1

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
Click Location & Routing(E44,L9)Location & Routingewd_type=routing;type=c,c;code=E44,L9 Click Connector(E44)Instrument Panel>Instrument Panel Wire / Radio Wiring Sub-Assy / Telephone Computer Wire>Air Conditioning Amplifier Assemblyewd_type=component;type=c;code=E44;pinno=7 Click Connector(L9)Instrument Panel>No. 2 Floor Wire>Refreshing Seat Switchewd_type=component;type=c;code=L9;pinno=8
E44-7 (LIN1) - L9-8 (SLIN)	Always	Below 1 Ω
E44-7 (LIN1) or L9-8 (SLIN) - Body ground	Always	10 kΩ or higher

Tester Connection

Condition

Specified Condition

Click Location & Routing(E44,L9)Location & Routingewd_type=routing;type=c,c;code=E44,L9

Click Connector(E44)Instrument Panel>Instrument Panel Wire / Radio Wiring Sub-Assy / Telephone Computer Wire>Air Conditioning Amplifier Assemblyewd_type=component;type=c;code=E44;pinno=7

Click Connector(L9)Instrument Panel>No. 2 Floor Wire>Refreshing Seat Switchewd_type=component;type=c;code=L9;pinno=8

E44-7 (LIN1) - L9-8 (SLIN)

Always

Below 1 Ω

E44-7 (LIN1) or L9-8 (SLIN) - Body ground

Always

10 kΩ or higher

Result:

Proceed to
OK
NG

Post-procedure1

None

5.INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY

Pre-procedure1

1.656,0.427 2.094,0.646 0.438,0.219 2.5,2.26 2.198,1.51 true 2.375,2.302 2.99,2.5 0.615,0.198 10 false LIN1 0.323,4 0.938,4.198 0.615,0.198 10 false GND 1.75,0.458 2.365,0.656 0.615,0.198 10 false E44 0.198,0.188 0.813,0.385 0.615,0.198 10 false *a

*a	Component with harness connected (Air Conditioning Amplifier Assembly)

Connect the E44 air conditioning amplifier assembly connector.

Turn the ignition switch to ON.

Procedure1

Using an oscilloscope, check the waveform.

OK:: Waveform is similar to that shown in the illustration.

Item	Content
Terminal No.	E44-7 (LIN1) - Body ground
Tool Setting	2 V/DIV., 20 ms./DIV.
Condition	Ignition switch ON

Result:

Proceed to
OK
NG

Post-procedure1

None

6.INSPECT FRONT SEAT HEATER SWITCH (REFRESHING SEAT SWITCH)

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

Click hereVehicle Interior>HEATING / AIR CONDITIONING>AIR CONDITIONING AMPLIFIER>REMOVAL202111,999999,_58,_111841,_0499808,RM100000001Z0AA,

6.INSPECT FRONT SEAT HEATER SWITCH (REFRESHING SEAT SWITCH)

Pre-procedure1

1.625,0.104 2.063,0.365 0.438,0.26 1.24,2.052 1.854,1.229 true 1.729,0.167 2.188,0.365 0.458,0.198 10 false L9 1.083,2.104 1.542,2.302 0.458,0.198 10 false SLIN 0.344,3.906 0.802,4.104 0.458,0.198 10 false GND 0.781,0.208 1.24,0.406 0.458,0.198 10 false *a

*a	Component with harness connected (Front Seat Heater Switch (Refreshing Seat Switch))

Connect the L9 front seat heater switch (refreshing seat switch) connector.

Turn the ignition switch to ON.

Procedure1

Using an oscilloscope, check the waveform.

Item	Content
Terminal No.	L9-8 (SLIN) - Body ground
Tool Setting	2 V/DIV., 20 ms./DIV.
Condition	Ignition switch ON

OK:: Waveform is similar to that shown in the illustration.

Result:

Proceed to
OK
NG

Post-procedure1

None

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

Click hereVehicle Interior>HEATING / AIR CONDITIONING>AIR CONDITIONING AMPLIFIER>REMOVAL202111,999999,_58,_111841,_0499808,RM100000001Z0AA,

REPLACE FRONT SEAT HEATER SWITCH (REFRESHING SEAT SWITCH)

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