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 [11/2023 - ]: Description

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This DTC is output when the clearance warning ECU assembly detects lost communication with the blind spot monitor sensor.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
U1177-87	Lost Communication with Side Obstacle Detection Control Module "A" (ch2) Missing Message	The clearance warning ECU assembly is unable to receive communication from the blind spot monitor sensor RH (A)	Open or short in CAN bus main wire or connector Open or short in CAN bus wire or connector Open or short in No. 22 junction connector Clearance warning ECU assembly Blind spot monitor sensor RH (A) Power source circuit of blind spot monitor sensor RH (A) Blind spot monitor sensor RH (A) ground circuit Blind spot monitor sensor LH (B)
U1178-87	Lost Communication with Side Obstacle Detection Control Module "B" (ch2) Missing Message	The clearance warning ECU assembly is unable to receive communication from the blind spot monitor sensor LH (B)	Open or short in CAN bus main wire or connector Open or short in CAN bus wire or connector Open or short in No. 22 junction connector Clearance warning ECU assembly Blind spot monitor sensor LH (B) Power source circuit of blind spot monitor sensor LH (B) Blind spot monitor sensor LH (B) ground circuit Blind spot monitor sensor RH (A)