Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM100000000VJWD
Model Year Start: 2016 Model: Sienna Prod Date Range: [12/2015 -           ]
Title: SEAT: REAR POWER SEAT CONTROL SYSTEM: Release Actuator Circuit; 2016 - 2020 MY Sienna [12/2015 -        ]

Release Actuator Circuit

DESCRIPTION

The fold seat control ECU receives a switch operation signal from the fold seat switch and activates the release actuator. The release actuator releases the lock of the stowed seat based on a drive voltage received from the ECU.

WIRING DIAGRAM

PROCEDURE

1.

CHECK FOLD SEAT CONTROL ECU

(a) Remove the fold seat control ECU with its connector still connected (See page 2016 - 2020 MY Sienna [12/2015 -        ]; SEAT: POWER SEAT CONTROL ECU(for Rear No. 2 Seat): REMOVAL ).

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

Standard Voltage:

LH Side

Tester Connection

Condition

Specified Condition

b3-3 (RACT) - Body ground

Engine switch off

Shift lever in P

Back door open

Stowing/Return switch on (Return)

11 to 14 V

RH Side

Tester Connection

Condition

Specified Condition

a3-3 (RACT) - Body ground

Engine switch off

Shift lever in P

Back door open

Stowing/Return switch on (Return)

11 to 14 V

Text in Illustration

*a

Component with harness connected

(Fold Seat Control ECU)

*b

LH Side

*c

RH Side

(c) Reinstall the fold seat control ECU.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

(See page 2016 MY Sienna [12/2015 - 08/2016]; SEAT: REAR POWER SEAT CONTROL SYSTEM: PROBLEM SYMPTOMS TABLE 2017 - 2020 MY Sienna [08/2016 -        ]; SEAT: REAR POWER SEAT CONTROL SYSTEM: PROBLEM SYMPTOMS TABLE )

NG

2.

CHECK HARNESS AND CONNECTOR (FOLD SEAT CONTROL ECU - RELEASE ACTUATOR)

(a) Disconnect the b3 or a3 fold seat control ECU connector.

(b) Disconnect the b1 or a1 No. 2 seat cushion frame sub-assembly (release actuator) connector.

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

Standard Resistance:

LH Side

Tester Connection

Condition

Specified Condition

b3-3 (RACT) - b1-7 (ACT)

Always

Below 1 Ω

b3-3 (RACT) - Body ground

Always

10 kΩ or higher

RH Side

Tester Connection

Condition

Specified Condition

a3-3 (RACT) - a1-7 (ACT)

Always

Below 1 Ω

a3-3 (RACT) - Body ground

Always

10 kΩ or higher

(d) Reconnect the No. 2 seat cushion frame sub-assembly (release actuator) connector.

(e) Reconnect the fold seat control ECU connector.

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

3.

CHECK HARNESS AND CONNECTOR (RELEASE ACTUATOR - BODY GROUND)

(a) Disconnect the b1 or a1 No. 2 seat cushion frame sub-assembly (release actuator) connector.

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

Standard Resistance:

LH Side

Tester Connection

Condition

Specified Condition

b1-4 (E) - Body ground

Always

Below 1 Ω

RH Side

Tester Connection

Condition

Specified Condition

a1-4 (E) - Body ground

Always

Below 1 Ω

Text in Illustration

*a

Front view of wire harness connector

(to No. 2 Seat Cushion Frame Sub-assembly (Release Actuator))

*b

LH Side

*c

RH Side

(c) Reconnect the No. 2 seat cushion frame sub-assembly (release actuator) connector.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

(See page 2016 MY Sienna [12/2015 - 08/2016]; SEAT: REAR POWER SEAT CONTROL SYSTEM: PROBLEM SYMPTOMS TABLE 2017 - 2020 MY Sienna [08/2016 -        ]; SEAT: REAR POWER SEAT CONTROL SYSTEM: PROBLEM SYMPTOMS TABLE )

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR