Toyota Tundra Service Manual: Terminals Of Ecu

TERMINALS OF ECU

1. CHECK DRIVER SIDE JUNCTION BLOCK ASSEMBLY, MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

(a) Remove the main body ECU (multiplex network body ECU) from the driver side junction block assembly.

Click here

(b) Connect the driver side junction block assembly connectors.

Tester Connection	Wiring Color	Terminal Description	Condition	Specified Condition
A-32 (IG) - Body ground	None - Body ground	Ignition power supply	Ignition switch ON	11 to 14 V
A-32 (IG) - Body ground	None - Body ground	Ignition power supply	Ignition switch off	Below 1 V
A-31 (BECU) - Body ground	None - Body ground	Battery power supply	Always	11 to 14 V
A-30 (ACC) - Body ground	None - Body ground	ACC power supply	Ignition switch ACC	11 to 14 V
A-30 (ACC) - Body ground	None - Body ground	ACC power supply	Ignition switch off	Below 1 V
A-11 (GND1) - Body ground	None - Body ground	Ground	Always	Below 1 Ω

(d) Install the main body ECU (multiplex network body ECU) to the driver side junction block assembly.

Click here

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

Tester Connection	Wiring Color	Terminal Description	Condition	Specified Condition
3J-41 (KSW) - Body ground	G - Body ground	Unlock warning switch assembly signal	No key in ignition key cylinder	11 to 14 V
3J-41 (KSW) - Body ground	G - Body ground	Unlock warning switch assembly signal	Key in ignition key cylinder	Below 1 V
J165-6 (FLCY) - Body ground	GR - Body ground	Front door courtesy light switch LH input	Front door LH open	Below 1 V
J165-6 (FLCY) - Body ground	GR - Body ground	Front door courtesy light switch LH input	Front door LH closed	Pulse generation

Toyota Tundra Service Manual > Occupant Classification System: Passenger Side Buckle Switch Circuit Malfunction (B1771)
DESCRIPTION The passenger side buckle switch circuit consists of the occupant classification ECU and the front seat inner belt RH. DTC B1771 is recorded when a malfunction is detected in the passenger side buckle switch circuit. Troubleshoot DTC B1771 first when DTCs B1771 and B1795 are output simul ...

Toyota Tundra Owners Manual