DTC C1380: Stop Light Control Relay Malfunction [06/2018 - 07/2019]: Description

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2024 Lexus ES 300h, 2023 Lexus ES 300h, 2022 Lexus ES 300h, 2021 Lexus ES 300h, and 2020 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.

When the skid control ECU (brake booster with master cylinder assembly) applies the brakes after receiving a brake request signal from the pre-collision system, dynamic radar cruise control system, secondary collision brake system or brake hold control system, the skid control ECU (brake booster with master cylinder assembly) operates the stop light control relay (stop light switch assembly) to illuminate the stop lights.

DTC No.	Detection Item	INF Code	DTC Detection Condition	Trouble Area	MIL	Note
C1380	Stop Light Control Relay Malfunction	761 762	INF Code: 761 When terminal IG1 voltage is 9.5 V or more, stop light drive output (STPO) is on and STP2 is off for 2 seconds or more. INF Code: 762 When terminal IG1 voltage is 9.5 V or more, stop light drive output (STPO) is off and the input signals for STP and STP2 differ for 5 seconds or more.	Wire harness or connector Stop light switch assembly Skid control ECU (brake booster with master cylinder assembly) Rear combination light assembly LH Rear combination light assembly RH Rear light assembly LH Rear light assembly RH Center stop light set Hybrid vehicle control ECU Certification ECU (smart key ECU assembly)	Does not come on	VSC DTC