Inspection Procedure

WARNING: This page is about a different car, the 2005 Toyota Sienna. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT FUSE (ECU-B)
1. Inspect the ECU-B fuse (See POWER SOURCE ).
1. NG: REPLACE FUSE
2. OK: GO TO NEXT STEP

READ VALUE OF HAND-HELD TESTER

Using the hand-held tester, check that the un-lock warning switch signal is output when the switch is operated.

Standard (Multiplex network body ECU):

STANDARD (MULTIPLEX NETWORK BODY ECU) SPECIFICATION

Item	Measurement Item/Display (Range)	Normal Condition	Diagnostic Note
KEY UNLK WRN SW	Un-lock warning switch signal/ON or OFF	ON: Key is in ignition key cylinder OFF: No key is in ignition key cylinder	-

OK: Go to step 5
NG: GO TO NEXT STEP

INSPECT UN-LOCK WARNING SWITCH ASSY

Remove the un-lock warning switch.

Inspect the resistance of the switch.

Standard:

UN-LOCK WARNING SWITCH

Terminal No.	Condition	Specified Condition
1 - 2	Free (Key removed)	10 KΩ or higher
1 - 2	Pushed (Key set)	Below 1 Ω

Fig 1: Inspecting Un-Lock Warning Switch Assy

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE UN-LOCK WARNING SWITCH ASSY
OK: GO TO NEXT STEP

CHECK WIRE HARNESS (UN-LOCK WARNING SWITCH ASSY - INSTRUMENT PANEL JUNCTION BLOCK ASSY (MULTIPLEX NETWORK BODY ECU))

Disconnect the K4 switch and B6 body ECU connectors.

Check the resistance between the wire harness side connectors.

Standard (Check for open circuit):

K4 SWITCH AND B6 BODY ECU CONNECTORS

Terminal No.	Specified Condition
K4-2 - B6-21 (KSW)	Below 1 Ω
K4-1 - Body ground	Below 1 Ω

Fig 2: Checking Wire Harness (Un-Lock Warning Switch - Instrument Panel Junction Block Assy (Multiplex Network Body ECU))

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR
OK: REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSY (MULTIPLEX NETWORK BODY ECU)

READ VALUE OF HAND-HELD TESTER
1. Using the hand-held tester, check that the driver side door courtesy lamp switch signal is output when the switch is operated.
  Standard (Multiplex network body ECU):
  
  Fig 3: Identifying Standard (Multiplex Network Body ECU) Specification Table
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
1. OK: REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSY (MULTIPLEX NETWORK BODY ECU)
2. NG: GO TO NEXT STEP

INSPECT FRONT DOOR COURTESY LAMP SWITCH ASSY (DRIVER SIDE)

Remove the courtesy lamp switch.

Inspect the resistance of the switch.

Standard:

FRONT DOOR COURTESY LAMP SWITCH ASSY (DRIVER SIDE)

Terminal No.	Condition	Specified Condition
1 - Body ground	Free	Below 1 Ω
1 - Body ground	Pushed	10 KΩ or higher

Fig 4: Inspecting Front Door Courtesy Lamp Switch Assy (Driver Side)

NG: REPLACE FRONT DOOR COURTESY LAMP SWITCH ASSY
OK: GO TO NEXT STEP

CHECK WIRE HARNESS (FRONT DOOR COURTESY LAMP SWITCH ASSY (DRIVER SIDE) -INSTRUMENT PANEL JUNCTION BLOCK ASSY (MULTIPLEX NETWORK BODY ECU))

Disconnect the D7 switch and B9 body ECU connectors.

Check the resistance between the wire harness side connectors.

Standard (Check for open circuit):

D7 SWITCH AND B9 BODY ECU CONNECTORS

Terminal No.	Specified Condition
D7-1 - B9-14 (DCTY)	Below 1 Ω

Fig 5: Checking Wire Harness (Front Door Courtesy Lamp Switch Assy (Driver Side) - Instrument Panel Junctin Block Assy (Multiplex Network Body ECU))

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR
OK: REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSY (MULTIPLEX NETWORK BODY ECU)