DTC U1177-87: Lost Communication with Side Obstacle Detection Control Module "A" (ch2) Missing Message; DTC U1178-87: Lost Communication with Side Obstacle Detection Control Module "B" (ch2) Missing Message [12/2024 - ]: Procedure
- CLEAR DTC
Result:
NEXT
See step 2
- CHECK FOR DTC
- Check for DTCs.
Body Electrical > Clearance Warning > Trouble Codes
Result
Result Proceed to Only U1177-87 is output A Only U1178-87 is output B U1177-87 and U1178-87 are output C None of the above conditions are met D
Result:
B
See step 5
Result:
C
See step 7
Result:
D
USE SIMULATION METHOD TO CHECK
Refer to METHOD TO SIMULATE PROBLEM SYMPTOMS [12/2024 - ]
Result:
A
See step 3
- Check for DTCs.
- CHECK HARNESS AND CONNECTOR (BLIND SPOT MONITOR SENSOR (A) - BODY GROUND)
Pre-procedure1
- Disconnect the connector of the blind spot monitor sensor (A).
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result S8-10 (BLGD) - Body ground Always Below 1 Ω Ω Result
Proceed to OK NG
Post-procedure1
- None
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 4
- CHECK HARNESS AND CONNECTOR (BLIND SPOT MONITOR SENSOR (A) - POWER SOURCE)
Pre-procedure1
- Disconnect the connector of the blind spot monitor sensor (A).
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Switch Condition Specified Condition Result S8-5 (BLB) - Body ground Ignition Switch ON 11 to 14 V V S8-5 (BLB) - Body ground Ignition switch off Below 1 V V Result
Proceed to OK NG
Post-procedure1
- None
Result:
OK
REPLACE BLIND SPOT MONITOR SENSOR (A)
Refer to REMOVAL [12/2024 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
- CHECK HARNESS AND CONNECTOR (BLIND SPOT MONITOR SENSOR (B) - BODY GROUND)
Pre-procedure1
- Disconnect the connector of the blind spot monitor sensor (B).
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result S7-10 (BRGD) - Body ground Always Below 1 Ω Ω Result
Proceed to OK NG
Post-procedure1
- None
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 6
- CHECK HARNESS AND CONNECTOR (BLIND SPOT MONITOR SENSOR (B) - POWER SOURCE)
Pre-procedure1
- Disconnect the blind spot monitor sensor (B).
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Switch Condition Specified Condition Result S7-5 (BRB) - Body ground Ignition switch ON 11 to 14 V V S7-5 (BRB) - Body ground Ignition switch off Below 1 V V Result
Proceed to OK NG
Post-procedure1
- None
Result:
OK
REPLACE BLIND SPOT MONITOR SENSOR (B)
Refer to REMOVAL [12/2024 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
- CHECK CAN BUS (CONFIRM PROBLEM SYMPTOMS)
Pre-procedure1
- Turn the ignition switch off.
- Disconnect the cable from the negative (-) auxiliary battery terminal.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition K58-37 (CANH) - K58-38 (CANL) Disconnect cable from negative (-) auxiliary battery terminal 54 to 69 Ω K58-37 (CANH) - Body ground Disconnect cable from negative (-) auxiliary battery terminal 200 Ω or higher K58-38 (CANL) - Body ground Disconnect cable from negative (-) auxiliary battery terminal 200 Ω or higher K58-37 (CANH) - K77-16 (BAT) Disconnect cable from negative (-) auxiliary battery terminal 6 kΩ or higher K58-38 (CANL) - K77-16 (BAT) Disconnect cable from negative (-) auxiliary battery terminal 6 kΩ or higher Result
Result Proceed to K58-37 (CANH) - K58-38 (CANL) is more than or equal to 70 Ω A K58-37 (CANH) - K58-38 (CANL) is less than or equal to 54 Ω B K58-37 (CANH) - Body ground is less than or equal to 200 Ω C K58-38 (CANL) - Body ground is less than or equal to 200 Ω D K58-37 (CANH) - K77-16 (BAT) is less than or equal to 6 kΩ E K58-38 (CANL) - K77-16 (BAT) is less than or equal to 6 kΩ F None of the above conditions are met G
Post-procedure1
- None
Result:
B
See step 12
Result:
C
See step 16
Result:
D
See step 16
Result:
E
See step 16
Result:
F
See step 16
Result:
G
See step 22
Result:
A
See step 8
- CHECK FOR OPEN IN CAN BUS WIRE (NO. 2 CAN JUNCTION CONNECTOR)
Pre-procedure1
- Disconnect the K108 No. 2 CAN junction connector.
*a Front view of wire harness connector
(to No. 2 CAN Junction Connector)*b to Clearance Warning ECU Assembly CAN Wire *c to Blind Spot Monitor Sensor (A) CAN Main Wire *d to Blind Spot Monitor Sensor (B) CAN Main Wire
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result K108-1 (CANH) - K108-5 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Ω K108-2 (CANH) - K108-6 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Ω K108-3 (CANH) - K108-7 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Ω Result
Result Proceed to OK A NG (to blind spot monitor sensor (A) CAN main wire) B NG (to blind spot monitor sensor (B) CAN main wire) C NG (to clearance warning ECU assembly CAN wire) D
Post-procedure1
- None
Result:
A
REPLACE NO. 2 CAN JUNCTION CONNECTOR
Result:
C
See step 10
Result:
D
See step 11
Result:
B
See step 9
- Disconnect the K108 No. 2 CAN junction connector.
- CHECK FOR OPEN IN CAN BUS MAIN WIRE (BLIND SPOT MONITOR SENSOR (A))
Pre-procedure1
- Reconnect the K108 No. 2 CAN junction connector.
- Disconnect the S8 blind spot monitor sensor (A) connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result S8-1 (CA2P) - S8-6 (CA2N) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Ω Result
Proceed to OK NG
Post-procedure1
- None
Result:
OK
REPLACE BLIND SPOT MONITOR SENSOR (A)
Refer to REMOVAL [12/2024 - ]
Result:
NG
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (BLIND SPOT MONITOR SENSOR LH (B) - NO. 2 CAN JUNCTION CONNECTOR)
- CHECK FOR OPEN IN CAN BUS MAIN WIRE (BLIND SPOT MONITOR SENSOR (B))
Pre-procedure1
- Reconnect the K108 No. 2 CAN junction connector.
- Disconnect the S7 blind spot monitor sensor (B) connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result S7-1 (CA2P) - S7-6 (CA2N) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Ω Result
Proceed to OK NG
Post-procedure1
- None
Result:
OK
REPLACE BLIND SPOT MONITOR SENSOR (B)
Refer to REMOVAL [12/2024 - ]
Result:
NG
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (BLIND SPOT MONITOR SENSOR RH (A) - NO. 2 CAN JUNCTION CONNECTOR)
- CHECK FOR OPEN IN CAN BUS WIRE (CLEARANCE WARNING ECU ASSEMBLY)
Pre-procedure1
- Reconnect the K108 No. 2 CAN junction connector.
- Disconnect the K58 clearance warning ECU assembly connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result K58-37 (CANH) - K58-38 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω Ω Result
Proceed to OK NG
Post-procedure1
- None
Result:
OK
REPLACE CLEARANCE WARNING ECU ASSEMBLY
Refer to REMOVAL [12/2024 - ]
Result:
NG
REPAIR OR REPLACE CAN BUS WIRE (CLEARANCE WARNING ECU ASSEMBLY - NO. 2 CAN JUNCTION CONNECTOR)
- CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 CAN JUNCTION CONNECTOR)
Pre-procedure1
- Disconnect the K108 No. 2 CAN junction connector.
*a Front view of wire harness connector
(to No. 2 CAN Junction Connector)*b to Clearance Warning ECU Assembly CAN Wire *c to Blind Spot Monitor Sensor (A) CAN Main Wire *d to Blind Spot Monitor Sensor (B) CAN Main Wire
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result K108-1 (CANH) - K108-5 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Ω K108-2 (CANH) - K108-6 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Ω K108-3 (CANH) - K108-7 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Ω Result
Result Proceed to OK A NG (to blind spot monitor sensor (A) CAN main wire) B NG (to blind spot monitor sensor (B) CAN main wire) C NG (to clearance warning ECU assembly CAN wire) D
Post-procedure1
- None
Result:
A
REPLACE NO. 2 CAN JUNCTION CONNECTOR
Result:
C
See step 14
Result:
D
See step 15
Result:
B
See step 13
- Disconnect the K108 No. 2 CAN junction connector.
- CHECK FOR SHORT IN CAN BUS WIRES (BLIND SPOT MONITOR SENSOR (A))
Pre-procedure1
- Reconnect the K108 No. 2 CAN junction connector.
- Disconnect the S8 blind spot monitor sensor (A) connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result S8-1 (CA2P) - S8-6 (CA2N) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Ω Result
Proceed to OK NG
Post-procedure1
- None
Result:
OK
REPLACE BLIND SPOT MONITOR SENSOR (A)
Refer to REMOVAL [12/2024 - ]
Result:
NG
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (BLIND SPOT MONITOR SENSOR LH (B) - NO. 2 CAN JUNCTION CONNECTOR)
- CHECK FOR SHORT IN CAN BUS WIRES (BLIND SPOT MONITOR SENSOR (B))
Pre-procedure1
- Reconnect the K108 No. 2 CAN junction connector.
- Disconnect the S7 blind spot monitor sensor (B) connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result S7-1 (CA2P) - S7-6 (CA2N) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Ω Result
Proceed to OK NG
Post-procedure1
- None
Result:
OK
REPLACE BLIND SPOT MONITOR SENSOR (B)
Refer to REMOVAL [12/2024 - ]
Result:
NG
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (BLIND SPOT MONITOR SENSOR RH (A) - NO. 2 CAN JUNCTION CONNECTOR)
- CHECK FOR SHORT IN CAN BUS WIRES (CLEARANCE WARNING ECU ASSEMBLY)
Pre-procedure1
- Reconnect the K108 No. 2 CAN junction connector.
- Disconnect the K58 clearance warning ECU assembly connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result K58-37 (CANH) - K58-38 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω Ω Result
Proceed to OK NG
Post-procedure1
- None
Result:
OK
REPLACE CLEARANCE WARNING ECU ASSEMBLY
Refer to REMOVAL [12/2024 - ]
Result:
NG
REPAIR OR REPLACE CAN BUS WIRE (CLEARANCE WARNING ECU ASSEMBLY - NO. 2 CAN JUNCTION CONNECTOR)
- CHECK FOR SHORT IN CAN BUS (BLIND SPOT MONITOR SENSOR (A) CONNECTION MAIN LINE)
Pre-procedure1
- Disconnect the K108 No. 2 CAN junction connector.
*1 DLC3 - - *a Front view of wire harness connector
(to No. 2 CAN Junction Connector)- -
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result K108-2 (CANH) - Body ground Disconnect cable from negative (-) auxiliary battery terminal 200 Ω or higher Ω K108-6 (CANL) - Body ground Disconnect cable from negative (-) auxiliary battery terminal 200 Ω or higher Ω K108-2 (CANH) - K77-16 (BAT) Disconnect cable from negative (-) auxiliary battery terminal 6 kΩ or higher kΩ K108-6 (CANL) - K77-16 (BAT) Disconnect cable from negative (-) auxiliary battery terminal 6 kΩ or higher kΩ HINT:
Check for short that was confirmed to be a malfunction by confirming symptoms.
Result
Proceed to OK NG
Post-procedure1
- None
Result:
NG
See step 21
Result:
OK
See step 17
- Disconnect the K108 No. 2 CAN junction connector.
- CHECK FOR SHORT IN CAN BUS (BLIND SPOT MONITOR SENSOR (B) CONNECTION MAIN LINE)
Pre-procedure1
- Disconnect the K108 No. 2 CAN junction connector.
*1 DLC3 - - *a Front view of wire harness connector
(to No. 2 CAN Junction Connector)- -
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result K108-3 (CANH) - Body ground Disconnect cable from negative (-) auxiliary battery terminal 200 Ω or higher Ω K108-7 (CANL) - Body ground Disconnect cable from negative (-) auxiliary battery terminal 200 Ω or higher Ω K108-3 (CANH) - K77-16 (BAT) Disconnect cable from negative (-) auxiliary battery terminal 6 kΩ or higher kΩ K108-7 (CANL) - K77-16 (BAT) Disconnect cable from negative (-) auxiliary battery terminal 6 kΩ or higher kΩ HINT:
Check for short that was confirmed to be a malfunction by confirming symptoms.
Result
Proceed to OK NG
Post-procedure1
- None
Result:
NG
See step 20
Result:
OK
See step 18
- Disconnect the K108 No. 2 CAN junction connector.
- CHECK FOR SHORT IN CAN BUS (CLEARANCE WARNING ECU ASSEMBLY CONNECTION BRANCH LINE)
Pre-procedure1
- Reconnect the K108 No. 2 CAN junction connector.
*1 DLC3 - - *a Front view of wire harness connector
(to No. 2 CAN Junction Connector)- -
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result K108-1 (CANH) - Body ground Disconnect cable from negative (-) auxiliary battery terminal 200 Ω or higher Ω K108-5 (CANL) - Body ground Disconnect cable from negative (-) auxiliary battery terminal 200 Ω or higher Ω K108-1 (CANH) - K77-16 (BAT) Disconnect cable from negative (-) auxiliary battery terminal 6 kΩ or higher kΩ K108-5 (CANL) - K77-16 (BAT) Disconnect cable from negative (-) auxiliary battery terminal 6 kΩ or higher kΩ HINT:
Check for short that was confirmed to be a malfunction by confirming symptoms.
Result
Proceed to OK NG
Post-procedure1
- None
Result:
OK
REPLACE NO. 2 CAN JUNCTION CONNECTOR
Result:
NG
See step 19
- Reconnect the K108 No. 2 CAN junction connector.
- CHECK FOR SHORT IN CAN BUS (CLEARANCE WARNING ECU ASSEMBLY)
Pre-procedure1
- Reconnect the K108 No. 2 CAN junction connector.
- Disconnect the K58 connector of the clearance warning ECU assembly.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result K58-37 (CANH) - Body ground Disconnect cable from negative (-) auxiliary battery terminal 200 Ω or higher Ω K58-38 (CANL) - Body ground Disconnect cable from negative (-) auxiliary battery terminal 200 Ω or higher Ω K58-37 (CANH) - K77-16 (BAT) Disconnect cable from negative (-) auxiliary battery terminal 6 kΩ or higher kΩ K58-38 (CANL) - K77-16 (BAT) Disconnect cable from negative (-) auxiliary battery terminal 6 kΩ or higher kΩ Result
Proceed to OK NG
Post-procedure1
- None
Result:
OK
REPLACE CLEARANCE WARNING ECU ASSEMBLY
Refer to REMOVAL [12/2024 - ]
Result:
NG
REPAIR OR REPLACE CAN BUS BRANCH LINE OR CONNECTOR (CLEARANCE WARNING ECU ASSEMBLY - NO. 2 CAN JUNCTION CONNECTOR)
- CHECK FOR SHORT IN CAN BUS (BLIND SPOT MONITOR SENSOR (B))
Pre-procedure1
- Reconnect the K108 No. 2 CAN junction connector.
- Disconnect the S7 blind spot monitor sensor (B).
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result S7-1 (CA2P) - Body ground Disconnect cable from negative (-) auxiliary battery terminal 200 Ω or higher Ω S7-6 (CA2N) - Body ground Disconnect cable from negative (-) auxiliary battery terminal 200 Ω or higher Ω S7-1 (CA2P) - K77-16 (BAT) Disconnect cable from negative (-) auxiliary battery terminal 6 kΩ or higher kΩ S7-6 (CA2N) - K77-16 (BAT) Disconnect cable from negative (-) auxiliary battery terminal 6 kΩ or higher kΩ Result
Proceed to OK NG
Post-procedure1
- None
Result:
OK
REPLACE BLIND SPOT MONITOR SENSOR (B)
Refer to REMOVAL [12/2024 - ]
Result:
NG
REPAIR OR REPLACE CAN BUS MAIN LINE OR CONNECTOR (BLIND SPOT MONITOR SENSOR RH (A) - NO. 2 CAN JUNCTION CONNECTOR)
- CHECK FOR SHORT IN CAN BUS (BLIND SPOT MONITOR SENSOR (A))
Pre-procedure1
- Reconnect the K108 No. 2 CAN junction connector.
- Disconnect the S8 blind spot monitor sensor (A) connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result S8-1 (CA2P) - Body ground Disconnect cable from negative (-) auxiliary battery terminal 200 Ω or higher Ω S8-6 (CA2N) - Body ground Disconnect cable from negative (-) auxiliary battery terminal 200 Ω or higher Ω S8-1 (CA2P) - K77-16 (BAT) Disconnect cable from negative (-) auxiliary battery terminal 6 kΩ or higher kΩ S8-6 (CA2N) - K77-16 (BAT) Disconnect cable from negative (-) auxiliary battery terminal 6 kΩ or higher kΩ Result
Proceed to OK NG
Post-procedure1
- None
Result:
OK
REPLACE BLIND SPOT MONITOR SENSOR (A) (B)
Refer to REMOVAL [12/2024 - ]
Result:
NG
REPAIR OR REPLACE CAN BUS MAIN LINE OR CONNECTOR (BLIND SPOT MONITOR SENSOR LH (B) - NO. 2 CAN JUNCTION CONNECTOR)
- CLEAR DTCS
- Using the GTS, clear the DTCs.
Body Electrical > Clearance Warning > Clear DTCs
Result
Proceed to NEXT
Result:
NEXT
See step 23
- Using the GTS, clear the DTCs.
- CHECK FOR DTC
- Check for DTCs.
Body Electrical > Clearance Warning > Trouble Codes
Result
Result Proceed to U1177-87 and U1178-87 are output A U1177-87 and U1178-87 are not output B
Result:
A
REPLACE CLEARANCE WARNING ECU ASSEMBLY
Refer to REMOVAL [12/2024 - ]
Result:
B
GO TO PROBLEM SYMPTOM SIMULATION METHOD
Refer to PROBLEM SYMPTOMS TABLE [12/2024 - ]
- Check for DTCs.