- Occupant classification ECU detects line short circuit signal, open circuit signal, short circuit to ground signal or short circuit to +B signal in passenger side buckle switch circuit for 2 seconds
- Passenger side buckle switch malfunction
- Occupant classification ECU malfunction
| Last Modified: 11-29-2007 | 1.6 C | |
| Service Category: Vehicle Interior | Section: Supplemental Restraint Systems | |
| Model Year: 2008 | Model: Sequoia | Doc ID: RM0000010V6032X |
| Title: SUPPLEMENTAL RESTRAINT SYSTEMS: OCCUPANT CLASSIFICATION SYSTEM: DESCRIPTION (2008 Sequoia) | ||
|
DTC |
B1771 |
Passenger Side Buckle Switch Circuit Malfunction |
DESCRIPTION
The passenger side buckle switch circuit consists of the occupant classification ECU and the front seat inner belt RH.
DTC B1771 is stored when a malfunction is detected in the passenger side buckle switch circuit.
Troubleshoot DTC B1771 first when DTCs B1771 and B1795 are output simultaneously.
|
DTC Code |
DTC Detection Condition |
Trouble Area |
|---|---|---|
|
B1771 |
One of following conditions is met: |
|
HINT:
- When DTC B1650/32 is detected as a result of troubleshooting the airbag system, perform troubleshooting for DTC B1771 of the occupant classification system.
- Use the Techstream to check for DTCs of the occupant classification ECU, otherwise the DTC cannot be read.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
After the ignition switch is turned off, the navigation system requires approximately 90 seconds to record various types of memory and settings. As a result, after turning the ignition switch off, wait 90 seconds or more before disconnecting the cable from the negative (-) battery terminal.
HINT:
- If troubleshooting (wire harness inspection) is difficult to perform, remove the front seat RH installation bolts to see the undersurface of the seat cushion.
- In the above case, hold the seat so that it does not fall down. Holding the seat for a long period of time may cause a problem, such as seat rail deformation. Hold the seat up only for as long as necessary.
PROCEDURE
|
1. |
CHECK FOR DTC |
(a) Turn the ignition switch to ON, and wait for at least 60 seconds.
(b) Clear the DTCs stored in the memory
.
HINT:
First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor.
(c) Turn the ignition switch off.
(d) Turn the ignition switch to ON, and wait for at least 60 seconds.
(e) Check for DTCs
.
OK:
DTC B1771 is not output.
HINT:
Codes other than DTC B1771 may be output at this time, but they are not related to this check.
|
|
2. |
CHECK CONNECTION OF CONNECTOR |
(a) Turn the ignition switch off.
(b) Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
(c) Check that the connectors are properly connected to the occupant classification ECU and the front seat inner belt RH.
OK:
Connectors are properly connected.
|
|
3. |
CHECK CONNECTOR |
(a) Disconnect the connectors from the occupant classification ECU and the front seat inner belt RH.
(b) Check that the connectors (on the occupant classification ECU side and front seat inner belt RH side) are not damaged
.
OK:
Connectors are not deformed or damaged.
HINT:
If the connectors are not connected securely, reconnect the connectors and proceed to the next inspection.
Result
|
Result |
Proceed to |
|---|---|
|
OK |
A |
|
NG (w/ Power seat) |
B |
|
NG (w/ Manual seat) |
C |
|
|
4. |
CHECK HARNESS AND CONNECTOR (OCCUPANT CLASSIFICATION ECU - FRONT SEAT INNER BELT RH) |
(a) Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
(b) Turn the ignition switch to ON, and wait for at least 60 seconds.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
for Power Seat
|
Tester Connection |
Switch Condition |
Specified Condition |
|---|---|---|
|
W6-9 (BSW) - Body ground |
Ignition switch ON |
Below 1 V |
|
W6-5 (BGND) - Body ground |
for Manual Seat
|
Tester Connection |
Switch Condition |
Specified Condition |
|---|---|---|
|
P14-9 (BSW) - Body ground |
Ignition switch ON |
Below 1 V |
|
P14-5 (BGND) - Body ground |
(d) Turn the ignition switch off.
(e) Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
(f) Using a service wire, connect terminals 1 (RBE-) and 2 (RBE+) of connector C.
NOTICE:
Do not forcibly insert the service wire into the terminals of the connector.
(g) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
for Power Seat
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
W6-9 (BSW) - W6-5 (BGND) |
Always |
Below 1 Ω |
for Manual Seat
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
P14-9 (BSW) - P14-5 (BGND) |
Always |
Below 1 Ω |
(h) Disconnect the service wire from connector C.
(i) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
for Power Seat
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
W6-9 (BSW) - Body ground |
Always |
1 MΩ or higher |
|
W6-5 (BGND) - Body ground |
||
|
W6-9 (BSW) - W6-5 (BGND) |
for Manual Seat
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
P14-9 (BSW) - Body ground |
Always |
1 MΩ or higher |
|
P14-5 (BGND) - Body ground |
||
|
P14-9 (BSW) - P14-5 (BGND) |
Result
|
Result |
Proceed to |
|---|---|
|
OK |
A |
|
NG (w/ Power seat) |
B |
|
NG (w/ Manual seat) |
C |
|
|
5. |
CHECK FOR DTC |
(a) Connect the connectors to the occupant classification ECU and the front seat inner belt RH.
(b) Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
(c) Turn the ignition switch to ON, and wait for at least 60 seconds.
(d) Clear the DTCs stored in the memory
.
HINT:
First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor.
(e) Turn the ignition switch off.
(f) Turn the ignition switch to ON, and wait for at least 60 seconds.
(g) Check for DTCs
.
OK:
DTC B1771 is not output.
HINT:
Codes other than DTC B1771 may be output at this time, but they are not related to this check.
|
|
6. |
REPLACE FRONT SEAT INNER BELT ASSEMBLY RH (PASSENGER SIDE BUCKLE SWITCH) |
(a) Turn the ignition switch off.
(b) Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
(c) Replace the front seat inner belt RH
.
HINT:
Perform the inspection using parts from a normal vehicle when possible.
(d) Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
|
|
7. |
CHECK FOR DTC |
(a) Turn the ignition switch to ON, and wait for at least 60 seconds.
(b) Clear the DTCs stored in the memory
.
HINT:
First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor.
(c) Turn the ignition switch off.
(d) Turn the ignition switch to ON, and wait for at least 60 seconds.
(e) Check for DTCs
.
OK:
DTC B1771 is not output.
HINT:
Codes other than DTC B1771 may be output at this time, but they are not related to this check.
|
|
9. |
REPLACE OCCUPANT CLASSIFICATION ECU |
(a) Turn the ignition switch off.
(b) Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
(c) Replace the occupant classification ECU.
-
for Power Seat
-
for Manual Seat
HINT:
Perform the inspection using parts from a normal vehicle when possible.
(d) Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
(e) Turn the ignition switch to ON, and wait for at least 60 seconds.
(f) Clear the DTCs stored in the memory
.
HINT:
If the DTCs are not cleared at this time, past DTCs will remain.
|
|
10. |
PERFORM ZERO POINT CALIBRATION |
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON, and wait for at least 60 seconds.
(c) Using the Techstream, perform the zero point calibration
.
|
|
11. |
PERFORM SENSITIVITY CHECK |
(a) Using the Techstream, perform the sensitivity check
.
Standard range:
27 to 33 kg (59.5 to 72.8 lb)
|
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