Terminals Of Ecu [08/2017 - ]

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CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) AND DRIVER SIDE JUNCTION BLOCK ASSEMBLY (w/ Rear Seat Belt Warning)

Disconnect the main body ECU (multiplex network body ECU) connectors.

Fig 1: Main Body ECU (Multiplex Network Body ECU) And Driver Side Junction Block Assembly (W/ Rear Seat Belt Warning) Connector End View

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*A	Main Body ECU (Multiplex Network Body ECU) with 1 Connector	-	-
*1	Main Body ECU (Multiplex Network Body ECU)	-	-
*a	1 Connector	-	-

Fig 2: Main Body ECU (Multiplex Network Body ECU) And Driver Side Junction Block Assembly (W/ Rear Seat Belt Warning) Connector End View

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*A	Main Body ECU (Multiplex Network Body ECU) with 2 Connectors	-	-
*1	Main Body ECU (Multiplex Network Body ECU)	-	-
*a	2 Connectors	-	-

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

HINT:

Measure the values on the wire harness side with the connector disconnected.

Tester Connection	Wiring Color	Terminal Description	Condition	Specified Condition
MB-30 (BECU) - Body ground	-	Battery power supply	Always	11 to 14 V
MB-32 (IG) - Body ground	-	Ignition power supply (IG signal)	Ignition switch ON → off	11 to 14 V → Below 1 V
MB-29 (ACC) - Body ground	-	Ignition power supply (ACC signal)	Ignition switch ACC → off	11 to 14 V → Below 1 V
MB-11 (GND1) - Body ground	-	Ground	Always	Below 1 Ω
E31-1 (LCTY) - Body ground	SB - Body ground	Rear door courtesy light switch (LH) input	Rear door LH closed (OFF)	10 kΩ or higher
E31-1 (LCTY) - Body ground	SB - Body ground	Rear door courtesy light switch (LH) input	Rear door LH open (ON)	Below 1 Ω
E31-6 (RCTY) - Body ground	LG - Body ground	Rear door courtesy light switch (RH) input	Rear door RH closed (OFF)	10 kΩ or higher
E31-6 (RCTY) - Body ground	LG - Body ground	Rear door courtesy light switch (RH) input	Rear door RH open (ON)	Below 1 Ω

CHECK COMBINATION METER ASSEMBLY

Disconnect the E43 and E47*2 combination meter assembly connectors.

Fig 3: Combination Meter Assembly Connector End View
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Terminal No. (Symbol)	Wiring Color	Terminal Description	Condition	Specified Condition
E43-40 (B) - Body ground	W - Body ground	Battery power supply	Always	11 to 14 V
E43-39 (IG+) - Body ground	P - Body ground	Ignition power supply	Ignition switch off	Below 1 V
E43-39 (IG+) - Body ground	P - Body ground	Ignition power supply	Ignition switch ON	11 to 14 V
E43-4 (EP) - Body ground	W-B - Body ground	Ground	Always	Below 1 Ω
E43-2 (RCMT) - Body ground1, 2	L - Body ground	Rear seat belt warning light center output signal	Ignition switch ON, rear seat belt warning light center off	11 to 14 V
E43-2 (RCMT) - Body ground1, 2	L - Body ground	Rear seat belt warning light center output signal	Ignition switch ON, rear seat belt warning light center on	Below 1 V
E43-3 (RRMT) - Body ground1, 2	G - Body ground	Rear seat belt warning light RH output signal	Ignition switch ON, rear seat belt warning light RH off	11 to 14 V
E43-3 (RRMT) - Body ground1, 2	G - Body ground	Rear seat belt warning light RH output signal	Ignition switch ON, rear seat belt warning light RH on	Below 1 V
E43-22 (RRSB) - Body ground1, 3	GR - Body ground	Rear right seat belt buckle switch signal	Ignition switch ON, rear seat belt RH unfastened	Below 1 V
E43-22 (RRSB) - Body ground1, 3	GR - Body ground	Rear right seat belt buckle switch signal	Ignition switch ON, rear seat belt RH fastened	11 to 14 V
E43-23 (RCSB) - Body ground1, 3	SB - Body ground	Rear center seat belt buckle switch signal	Ignition switch ON, rear seat belt center unfastened	Below 1 V
E43-23 (RCSB) - Body ground1, 3	SB - Body ground	Rear center seat belt buckle switch signal	Ignition switch ON, rear seat belt center fastened	11 to 14 V
E43-24 (RLSB) - Body ground*1	V - Body ground	Rear left seat belt buckle switch signal	Ignition switch ON, rear seat belt LH unfastened	Below 1 V
E43-24 (RLSB) - Body ground*1	V - Body ground	Rear left seat belt buckle switch signal	Ignition switch ON, rear seat belt LH fastened	11 to 14 V
E43-25 (RCSB) - Body ground1, 2	SB - Body ground	Rear center seat belt buckle switch signal	Ignition switch ON, rear seat belt center unfastened	Below 1 V
E43-25 (RCSB) - Body ground1, 2	SB - Body ground	Rear center seat belt buckle switch signal	Ignition switch ON, rear seat belt center fastened	11 to 14 V
E43-25 (RLMT) - Body ground1, 3	B - Body ground	Rear seat belt warning light LH output signal	Ignition switch ON, rear seat belt warning light LH off	11 to 14 V
E43-25 (RLMT) - Body ground1, 3	B - Body ground	Rear seat belt warning light LH output signal	Ignition switch ON, rear seat belt warning light LH on	Below 1 V
E43-26 (RRSB) - Body ground1, 2	GR - Body ground	Rear right seat belt buckle switch signal	Ignition switch ON, rear seat belt RH unfastened	Below 1 V
E43-26 (RRSB) - Body ground1, 2	GR - Body ground	Rear right seat belt buckle switch signal	Ignition switch ON, rear seat belt RH fastened	11 to 14 V
E43-26 (RCMT) - Body ground1, 3	L - Body ground	Rear seat belt warning light center output signal	Ignition switch ON, rear seat belt warning light center off	11 to 14 V
E43-26 (RCMT) - Body ground1, 3	L - Body ground	Rear seat belt warning light center output signal	Ignition switch ON, rear seat belt warning light center on	Below 1 V
E43-27 (RRMT) - Body ground1, 3	G - Body ground	Rear seat belt warning light RH output signal	Ignition switch ON, rear seat belt warning light RH off	11 to 14 V
E43-27 (RRMT) - Body ground1, 3	G - Body ground	Rear seat belt warning light RH output signal	Ignition switch ON, rear seat belt warning light RH on	Below 1 V
E47-8 (RLMT) - Body ground1, 2	B - Body ground	Rear seat belt warning light LH output signal	Ignition switch ON, rear seat belt warning light LH off	11 to 14 V
E47-8 (RLMT) - Body ground1, 2	B - Body ground	Rear seat belt warning light LH output signal	Ignition switch ON, rear seat belt warning light LH on	Below 1 V

*1: w/ Rear Seat Belt Warning
*2: for Multi-information Display (Color Type)
*3: for Multi-information Display (Segment LCD Type and Dot LCD Type)

AIRBAG SENSOR ASSEMBLY

Fig 4: Airbag Sensor Assembly Connector End View

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Terminal No.	Terminal Symbol	Destination
L11-12	LBE-	Front seat inner belt assembly LH
L11-11	LBE+	Front seat inner belt assembly LH
L47-13	FSR-	Occupant detection ECU
L47-12	FSR+	Occupant detection ECU

CHECK OCCUPANT DETECTION ECU

Measure the voltage and check for pulses according to the value(s) in the table below.

Fig 5: Occupant Detection ECU Connector End View

for TMMMS Made

for TMMC Made

FOR TMMMS MADE

Tester Connection	Wiring Color	Terminal Description	Condition	Specified Condition
S2-1 (+B) - S2-3 (GND)	W - W-B	Battery	Always	11 to 14 V
S2-2 (DIA)	GR	Diagnosis (DLC3)	-*	-*
S2-3 (GND) - Body ground	W-B - Body ground	Ground	Always	Below 1 V
S2-4 (FSR-) - S2-3 (GND)	LG - W-B	Airbag sensor assembly communication line	Always	Below 1 V
S2-5 (BGND) - S2-3 (GND)	P - W-B	Front passenger buckle switch ground line	Always	Below 1 V
S2-6 (IG2) - S2-3 (GND)	B - W-B	Power source	Ignition switch ON	11 to 14 V
S2-7 (FSR+) - S2-4 (FSR-)	L - LG	Airbag sensor assembly communication line	Ignition switch ON	Pulse generation
S2-8 (BSW) - S2-5 (BGND)	G - P	Front passenger buckle switch line	Always	Pulse generation
S1-2 (SVC3) - S1-6 (SGD3)	GR - W	Occupant classification sensor LH power supply line	Ignition switch ON	4.9 to 5.1 V
S1-1 (SVC1) - S1-5 (SGD1)	R - G	Occupant classification sensor RH power supply line	Ignition switch ON	4.9 to 5.1 V
S1-4 (SIG3) - S1-6 (SGD3)	SB - W	Occupant classification sensor LH signal line	Ignition switch ON	Pulse generation
S1-3 (SIG1) - S1-5 (SGD1)	P - G	Occupant classification sensor RH signal line	Ignition switch ON	Pulse generation
S1-6 (SGD3) - S2-3 (GND)	W - W-B	Occupant classification sensor LH ground line	Always	Below 1 V
S1-5 (SGD1) - S2-3 (GND)	G - W-B	Occupant classification sensor RH ground line	Always	Below 1 V

FOR TMMC MADE

Tester Connection	Wiring Color	Terminal Description	Condition	Specified Condition
S2-1 (+B) - S2-3 (GND)	W - W-B	Battery	Always	11 to 14 V
S2-2 (DIA)	GR	Diagnosis (DLC3)	-*	-*
S2-3 (GND) - Body ground	W-B - Body ground	Ground	Always	Below 1 V
S2-4 (FSR-) - S2-3 (GND)	Y - W-B	Airbag sensor assembly communication line	Always	Below 1 V
S2-5 (BGND) - S2-3 (GND)	P - W-B	Front passenger buckle switch ground line	Always	Below 1 V
S2-6 (IG2) - S2-3 (GND)	B - W-B	Power source	Ignition switch ON	11 to 14 V
S2-7 (FSR+) - S2-4 (FSR-)	L - Y	Airbag sensor assembly communication line	Ignition switch ON	Pulse generation
S2-8 (BSW) - S2-5 (BGND)	G - P	Front passenger buckle switch line	Always	Pulse generation
S7-2 (SVC3) - S7-6 (SGD3)	GR - W	Occupant classification sensor LH power supply line	Ignition switch ON	4.9 to 5.1 V
S7-1 (SVC1) - S7-5 (SGD1)	R - G	Occupant classification sensor RH power supply line	Ignition switch ON	4.9 to 5.1 V
S7-4 (SIG3) - S7-6 (SGD3)	Y - W	Occupant classification sensor LH signal line	Ignition switch ON	Pulse generation
S7-3 (SIG1) - S7-5 (SGD1)	P - G	Occupant classification sensor RH signal line	Ignition switch ON	Pulse generation
S7-6 (SGD3) - S2-3 (GND)	W - W-B	Occupant classification sensor LH ground line	Always	Below 1 V
S7-5 (SGD1) - S2-3 (GND)	G - W-B	Occupant classification sensor RH ground line	Always	Below 1 V

*: As this is a line that is connected to other systems, voltage changes according to the systems that are connected.

If the result is not as specified, the occupant detection ECU may be malfunctioning.