| Last Modified: 11-20-2023 | 6.11:8.1.0 | Doc ID: RM100000001SISQ |
| Model Year Start: 2021 | Model: Camry | Prod Date Range: [10/2020 - ] |
| Title: SEAT BELT: SEAT BELT WARNING SYSTEM: Rear Seat Belt Warning Light Malfunction; 2021 - 2024 MY Camry [10/2020 - ] | ||
|
Rear Seat Belt Warning Light Malfunction |
DESCRIPTION
The main body ECU (multiplex network body ECU) detects whether either the rear doors are open or closed based on the courtesy light switch condition and then sends the rear door status signal to the combination meter assembly. The combination meter assembly detects the rear seat belt state. The rear seat belt warning light on the telltale light assembly illuminates, blinks or turns off in accordance with the rear door state, vehicle speed and rear seat belt state.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
-
The seat belt warning system uses the CAN communication system. First, confirm that there is no malfunction in the CAN communication system. Refer to the How to Proceed with Troubleshooting procedure.
Click here
![2018 - 2024 MY Camry [03/2017 - ]; SEAT BELT: SEAT BELT WARNING SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING](/t3Portal/stylegraphics/info.gif)
- Inspect the fuses for circuits related to this system before performing the following procedure.
PROCEDURE
|
1. |
READ VALUE USING TECHSTREAM (REAR DOOR COURTESY LIGHT SWITCH) |
(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 / Main Body / Data List.
(e) Read the Data List according to the display on the Techstream.
Body Electrical > Main Body > Data List
|
Tester Display |
Measurement Item |
Range |
Normal Condition |
Diagnostic Note |
|---|---|---|---|---|
|
RR Door Courtesy SW |
Rear door courtesy light switch RH |
ON or OFF |
ON: Rear door RH open OFF: Rear door RH closed |
- |
|
RL Door Courtesy SW |
Rear door courtesy light switch LH |
ON or OFF |
ON: Rear door LH open OFF: Rear door LH closed |
- |
Body Electrical > Main Body > Data List
|
Tester Display |
|---|
|
RR Door Courtesy SW |
|
RL Door Courtesy SW |
OK:
The Techstream display changes correctly in response to the rear door condition.
| NG |
|
|
|
2. |
CHECK REAR SEAT BELT WARNING |
|
(a) Check the rear seat belt warning function. Click here
|
|
|
Result |
Proceed to |
|---|---|
|
The rear seat belt warning lights operation is normal |
A |
|
The rear seat belt warning lights (all seats) do not operate normally |
B |
|
The rear seat belt warning light (RH) does not operate normally |
C |
|
The rear seat belt warning light (center) does not operate normally |
D |
|
The rear seat belt warning light (LH) does not operate normally |
E |
| A |
|
| C |
|
| D |
|
| E |
|
|
|
3. |
PERFORM ACTIVE TEST USING TECHSTREAM (REAR SEAT BELT WARNING LIGHT) |
(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 / Combination Meter / Active Test.
(e) Perform the Active Test according to the display on the Techstream.
Body Electrical > Combination Meter > Active Test
|
Tester Display |
Measurement Item |
Control Range |
Diagnostic Note |
|---|---|---|---|
|
Rear Seat Belt Warning |
Rear seat belt warning light |
OFF/ON |
- |
Body Electrical > Combination Meter > Active Test
|
Tester Display |
|---|
|
Rear Seat Belt Warning |
|
Result |
Proceed to |
|---|---|
|
The rear seat belt warning light does not operate normally |
A |
|
The rear seat belt warning light operates normally |
B |
| B |
|
|
|
4. |
CHECK HARNESS AND CONNECTOR (BATTERY - TELLTALE LIGHT ASSEMBLY) |
(a) Disconnect the K36 telltale light assembly connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
K36-10 (IG+) - Body ground |
Ignition switch ON |
11 to 14 V |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
5. |
CHECK HARNESS AND CONNECTOR (TELLTALE LIGHT ASSEMBLY - COMBINATION METER ASSEMBLY) |
(a) Reconnect the K36 telltale light assembly connector.
(b) Disconnect the K21 combination meter assembly connector.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
K21-18 (RLMT) - Body ground |
Ignition switch ON |
11 to 14 V |
|
K21-19 (RCMT) - Body ground |
Ignition switch ON |
11 to 14 V |
|
K21-20 (RRMT) - Body ground |
Ignition switch ON |
11 to 14 V |
| OK |
|
| NG |
|
|
6. |
READ VALUE USING TECHSTREAM (REAR SEAT BELT BUCKLE SWITCH (FOR RH)) |
(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 / Combination Meter / Data List.
(e) Read the Data List according to the display on the Techstream.
Body Electrical > Combination Meter > Data List
|
Tester Display |
Measurement Item |
Range |
Normal Condition |
Diagnostic Note |
|---|---|---|---|---|
|
Rear Right Seat Buckle / Occupant Detection Warning Switch |
Rear seat inner with center belt RH buckle signal |
ON or OFF |
OFF: Rear RH seat belt fastened ON: Rear RH seat belt not fastened |
- |
Body Electrical > Combination Meter > Data List
|
Tester Display |
|---|
|
Rear Right Seat Buckle / Occupant Detection Warning Switch |
|
Result |
Proceed to |
|---|---|
|
ON or OFF does not appear on the tester screen according to the rear seat belt condition |
A |
|
ON or OFF appears on the tester screen according to the rear seat belt condition |
B |
| B |
|
|
|
7. |
CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - REAR SEAT INNER WITH CENTER BELT ASSEMBLY RH - BODY GROUND) |
(a) Disconnect the K21 combination meter assembly connector.
(b) Disconnect the R72 rear seat inner with center belt assembly RH connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
K21-26 (RRSB) - R72-5 |
Always |
Below 1 Ω |
|
K21-26 (RRSB) or R72-5 - Body ground |
Always |
10 kΩ or higher |
|
R72-4 - Body ground |
Always |
Below 1 Ω |
| OK |
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
8. |
PERFORM ACTIVE TEST USING TECHSTREAM (REAR SEAT BELT WARNING LIGHT) |
(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 / Combination Meter / Active Test.
(e) Perform the Active Test according to the display on the Techstream.
Body Electrical > Combination Meter > Active Test
|
Tester Display |
Measurement Item |
Control Range |
Diagnostic Note |
|---|---|---|---|
|
Rear Seat Belt Warning |
Rear seat belt warning light |
OFF/ON |
- |
Body Electrical > Combination Meter > Active Test
|
Tester Display |
|---|
|
Rear Seat Belt Warning |
|
Result |
Proceed to |
|---|---|
|
The rear seat belt warning light does not operate normally |
A |
|
The rear seat belt warning light operates normally |
B |
| B |
|
|
|
9. |
CHECK HARNESS AND CONNECTOR (TELLTALE LIGHT ASSEMBLY - COMBINATION METER ASSEMBLY) |
(a) Disconnect the K21 combination meter assembly connector.
(b) Disconnect the K36 telltale light assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
K21-20 (RRMT) - K36-3 (RRID) |
Always |
Below 1 Ω |
|
K21-20 (RRMT) or K36-3 (RRID) - Body ground |
Always |
10 kΩ or higher |
| OK |
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
10. |
READ VALUE USING TECHSTREAM (REAR SEAT BELT BUCKLE SWITCH (FOR CENTER)) |
(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 / Combination Meter / Data List.
(e) Read the Data List according to the display on the Techstream.
Body Electrical > Combination Meter > Data List
|
Tester Display |
Measurement Item |
Range |
Normal Condition |
Diagnostic Note |
|---|---|---|---|---|
|
Rear Center Seat Buckle / Occupant Detection Warning Switch |
Rear seat inner with center belt LH (for center) buckle signal |
ON or OFF |
OFF: Rear LH seat belt (for center) fastened ON: Rear LH seat belt (for center) not fastened |
- |
Body Electrical > Combination Meter > Data List
|
Tester Display |
|---|
|
Rear Center Seat Buckle / Occupant Detection Warning Switch |
|
Result |
Proceed to |
|---|---|
|
ON or OFF does not appear on the tester screen according to the rear seat belt condition |
A |
|
ON or OFF appears on the tester screen according to the rear seat belt condition |
B |
| B |
|
|
|
11. |
CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - REAR SEAT INNER WITH CENTER BELT ASSEMBLY LH (FOR CENTER) - BODY GROUND) |
(a) Disconnect the K21 combination meter assembly connector.
(b) Disconnect the R74 rear seat inner with center belt assembly LH (for center) connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
K21-25 (RCSB) - R74-1 |
Always |
Below 1 Ω |
|
K21-25 (RCSB) or R74-1 - Body ground |
Always |
10 kΩ or higher |
|
R74-2 - Body ground |
Always |
Below 1 Ω |
| OK |
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
12. |
PERFORM ACTIVE TEST USING TECHSTREAM (REAR SEAT BELT WARNING LIGHT) |
(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 / Combination Meter / Active Test.
(e) Perform the Active Test according to the display on the Techstream.
Body Electrical > Combination Meter > Active Test
|
Tester Display |
Measurement Item |
Control Range |
Diagnostic Note |
|---|---|---|---|
|
Rear Seat Belt Warning |
Rear seat belt warning light |
OFF/ON |
- |
Body Electrical > Combination Meter > Active Test
|
Tester Display |
|---|
|
Rear Seat Belt Warning |
|
Result |
Proceed to |
|---|---|
|
The rear seat belt warning light does not operate normally |
A |
|
The rear seat belt warning light operates normally |
B |
| B |
|
|
|
13. |
CHECK HARNESS AND CONNECTOR (TELLTALE LIGHT ASSEMBLY - COMBINATION METER ASSEMBLY) |
(a) Disconnect the K21 combination meter assembly connector.
(b) Disconnect the K36 telltale light assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
K21-19 (RCMT) - K36-2 (RCID) |
Always |
Below 1 Ω |
|
K21-19 (RCMT) or K36-2 (RCID) - Body ground |
Always |
10 kΩ or higher |
| OK |
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
14. |
READ VALUE USING TECHSTREAM (REAR SEAT BELT BUCKLE SWITCH (FOR LH)) |
(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 / Combination Meter / Data List.
(e) Read the Data List according to the display on the Techstream.
Body Electrical > Combination Meter > Data List
|
Tester Display |
Measurement Item |
Range |
Normal Condition |
Diagnostic Note |
|---|---|---|---|---|
|
Rear Left Seat Buckle / Occupant Detection Warning Switch |
Rear seat inner with center belt LH (for LH) buckle signal |
ON or OFF |
OFF: Rear LH seat belt (for LH) fastened ON: Rear LH seat belt (for LH) not fastened |
- |
Body Electrical > Combination Meter > Data List
|
Tester Display |
|---|
|
Rear Left Seat Buckle / Occupant Detection Warning Switch |
|
Result |
Proceed to |
|---|---|
|
ON or OFF does not appear on the tester screen according to the rear seat belt condition |
A |
|
ON or OFF appears on the tester screen according to the rear seat belt condition |
B |
| B |
|
|
|
15. |
CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - REAR SEAT INNER WITH CENTER BELT ASSEMBLY LH (FOR LH) - BODY GROUND) |
(a) Disconnect the K21 combination meter assembly connector.
(b) Disconnect the R73 rear seat inner with center belt assembly LH (for LH) connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
K21-24 (RLSB) - R73-5 |
Always |
Below 1 Ω |
|
K21-24 (RLSB) or R73-5 - Body ground |
Always |
10 kΩ or higher |
|
R73-4 - Body ground |
Always |
Below 1 Ω |
| OK |
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
16. |
PERFORM ACTIVE TEST USING TECHSTREAM (REAR SEAT BELT WARNING LIGHT) |
(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 / Combination Meter / Active Test.
(e) Perform the Active Test according to the display on the Techstream.
Body Electrical > Combination Meter > Active Test
|
Tester Display |
Measurement Item |
Control Range |
Diagnostic Note |
|---|---|---|---|
|
Rear Seat Belt Warning |
Rear seat belt warning light |
OFF/ON |
- |
Body Electrical > Combination Meter > Active Test
|
Tester Display |
|---|
|
Rear Seat Belt Warning |
|
Result |
Proceed to |
|---|---|
|
The rear seat belt warning light does not operate normally |
A |
|
The rear seat belt warning light operates normally |
B |
| B |
|
|
|
17. |
CHECK HARNESS AND CONNECTOR (TELLTALE LIGHT ASSEMBLY - COMBINATION METER ASSEMBLY) |
(a) Disconnect the K21 combination meter assembly connector.
(b) Disconnect the K36 telltale light assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
K21-18 (RLMT) - K36-1 (RLID) |
Always |
Below 1 Ω |
|
K21-18 (RLMT) or K36-1 (RLID) - Body ground |
Always |
10 kΩ or higher |
| OK |
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|