DESCRIPTION
The occupant classification sensor front LH circuit consists of the occupant detection ECU and the occupant classification sensor front LH.
DTC B1780 is set when a malfunction is detected in the occupant classification sensor front LH circuit.
DTC No. |
DTC Detecting Conditions |
Trouble Areas |
---|---|---|
B1780 |
|
|
HINT:
WIRING DIAGRAM
CAUTION / NOTICE / HINT
HINT:
PROCEDURE
1. |
CHECK DTC |
(a) Turn the ignition switch to the ON position.
(b) Clear any DTCs stored in the memory (See page
).
HINT:
(c) Turn the ignition switch to the LOCK position.
(d) Turn the ignition switch to the ON position.
(e) Using the Techstream, check for DTCs of the occupant detection ECU (See page
).
OK:
DTC B1780 is not output.
HINT:
DTCs other than B1780 may be output at this time, but they are not related to this check.
OK | ![]() |
PERFORM SENSITIVITY CHECK |
|
2. |
CHECK CONNECTION OF CONNECTORS |
(a) Turn the ignition switch to the LOCK position.
(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
(c) Check that the connectors are properly connected to the occupant detection ECU and the occupant classification sensor front LH.
OK:
The connectors are properly connected.
NG | ![]() |
CONNECT CONNECTORS |
|
3. |
CHECK CONNECTORS |
(a) Check that the connectors (on the occupant detection ECU side and occupant
classification sensor front LH side) are not damaged (See page
).
OK:
The connectors are not deformed or damaged.
NG | ![]() |
REPAIR OR REPLACE WIRE HARNESS |
|
4. |
CHECK NO. 1 SEAT WIRE (TO B+) |
(a) Disconnect the connectors from the occupant detection ECU and the occupant classification sensor front LH. |
|
(b) Connect the negative (-) terminal cable to the battery.
(c) Turn the ignition switch to the ON position.
(d) Measure the voltage.
Standard voltage:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
O4-1 (SGD1) - Body ground |
Ignition switch ON |
Below 1 V |
O4-7 (SIG1) - Body ground |
Ignition switch ON |
Below 1 V |
O4-11 (SVC1) - Body ground |
Ignition switch ON |
Below 1 V |
NG | ![]() |
REPAIR OR REPLACE NO. 1 SEAT WIRE |
|
5. |
CHECK NO. 1 SEAT WIRE (FOR OPEN) |
(a) Turn the ignition switch to the LOCK position. |
|
(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
(c) Using service wires, connect O6-1 (SVC1) and O6-3 (SGD1), and connect O6-2 (SIG1) and O6-3 (SGD1) of connector C.
NOTICE:
Do not forcibly insert the service wires into the terminals of the connector when connecting.
(d) Measure the resistance.
Standard resistance:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
O4-7 (SIG1) - O4-1 (SGD1) |
Always |
Below 1 Ω |
O4-11 (SVC1) - O4-1 (SGD1) |
Always |
Below 1 Ω |
NG | ![]() |
REPAIR OR REPLACE NO. 1 SEAT WIRE |
|
6. |
CHECK NO. 1 SEAT WIRE (FOR SHORT) |
(a) Disconnect the service wires from connector C. |
|
(b) Measure the resistance.
Standard resistance:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
O4-7 (SIG1) - O4-1 (SGD1) |
Always |
1 MΩ or higher |
O4-11 (SVC1) - O4-1 (SGD1) |
Always |
1 MΩ or higher |
O4-7 (SIG1) - O4-11 (SVC1) |
Always |
1 MΩ or higher |
NG | ![]() |
REPAIR OR REPLACE NO. 1 SEAT WIRE |
|
7. |
CHECK NO. 1 SEAT WIRE (TO GROUND) |
(a) Measure the resistance.
Standard resistance:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
O4-1 (SGD1) - Body ground |
Always |
1 MΩ or higher |
O4-7 (SIG1) - Body ground |
Always |
1 MΩ or higher |
O4-11 (SVC1) - Body ground |
Always |
1 MΩ or higher |
NG | ![]() |
REPAIR OR REPLACE NO. 1 SEAT WIRE |
|
8. |
CHECK DTC |
(a) Connect the connectors to the occupant detection ECU and the occupant classification sensor front LH.
(b) Connect the negative (-) terminal cable to the battery.
(c) Turn the ignition switch to the ON position.
(d) Clear any DTCs stored in the memory (See page
).
HINT:
(e) Turn the ignition switch to the LOCK position.
(f) Turn the ignition switch to the ON position.
(g) Using the Techstream, check for DTCs of the occupant detection ECU (See page
).
OK:
DTC B1780 is not output.
HINT:
DTCs other than B1780 may be output at this time, but they are not related to this check.
OK | ![]() |
USE SIMULATION METHOD TO CHECK |
|
9. |
REPLACE OCCUPANT DETECTION ECU |
(a) Turn the ignition switch to the LOCK position.
(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
(c) Replace the occupant detection ECU (See page
).
HINT:
Perform the inspection using parts from a normal vehicle when possible.
|
10. |
PERFORM ZERO POINT CALIBRATION |
(a) Connect the negative (-) terminal cable to the battery.
(b) Connect the Techstream to the DLC3.
(c) Turn the ignition switch to the ON position.
(d) Using the Techstream, perform the zero point calibration (See page
).
OK:
"Zero Point Calibration is complete." is displayed on the Techstream.
NG | ![]() |
GO TO STEP 13 |
|
11. |
PERFORM SENSITIVITY CHECK |
(a) Using the Techstream, perform the sensitivity check (See page
).
Standard value:
27 to 33 kg (59.52 to 72.75 lb)
NG | ![]() |
GO TO STEP 13 |
|
12. |
CHECK DTC |
(a) Connect the negative (-) terminal cable to the battery.
(b) Turn the ignition switch to the ON position.
(c) Clear any DTCs stored in the memory (See page
).
HINT:
(d) Turn the ignition switch to the LOCK position.
(e) Turn the ignition switch to the ON position.
(f) Using the Techstream, check for DTCs of the occupant detection ECU (See page
).
OK:
DTC B1780 is not output.
HINT:
DTCs other than B1780 may be output at this time, but they are not related to this check.
OK | ![]() |
USE SIMULATION METHOD TO CHECK |
|
13. |
REPLACE FRONT SEAT WITH ADJUSTER FRAME ASSEMBLY RH |
(a) Turn the ignition switch to the LOCK position.
(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
(c) Replace the front seat with adjuster frame assembly RH (See page
).
|
14. |
PERFORM ZERO POINT CALIBRATION |
(a) Connect the negative (-) terminal cable to the battery.
(b) Connect the Techstream to the DLC3.
(c) Turn the ignition switch to the ON position.
(d) Using the Techstream, perform the zero point calibration (See page
).
OK:
"Zero Point Calibration is complete." is displayed on the Techstream.
|
15. |
PERFORM SENSITIVITY CHECK |
(a) Using the Techstream, perform the sensitivity check (See page
).
Standard value:
27 to 33 kg (59.52 to 72.75 lb)
NEXT | ![]() |
USE SIMULATION METHOD TO CHECK |
Operation Check
OPERATION CHECK
1. CHECK WINDOW LOCK FUNCTION
(a) Turn the ignition switch ON.
(b) Press the window lock switch of the power window regulator master switch
assembly.
HINT:
The illumination (LED) built into the switch knob of each seat does not turn
off.
(c) Check that the power window fo ...
Dtc Check / Clear
DTC CHECK / CLEAR
1. DTC CHECK USING TECHSTREAM
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Air Conditioner / Trouble Codes.
(e) Check for DTCs.
2. DTC CLEAR USING TECHSTREAM
(a) Conn ...
Components
COMPONENTS
ILLUSTRATION
*A
for Type A
*B
for Type B
*C
for Type C
-
-
*1
MILLIMETER WAVE RADAR SENSOR ASSEMBLY
*2
MILLIMETER WAVE RADAR WIRE
...