2008 Lexus IS FFACTORY OEM SERVICE PROCEDURE

DTC C1380/64 Stop Light Control Relay Malfunction: Description

Upon receiving the hill-start assist control or the dynamic radar cruise control (for vehicles with the dynamic radar cruise control) operating signal from the skid control ECU, the relay contact turns on and the stop light comes on.

DTC DETECTION CONDITION

DTC Code DTC Detection Condition Trouble Area
C1380/64 Either of the following is detected
  1. When the stop light control (BRK-LP) relay drive output (STPO) is ON, the relay contact remains open (signal is not input to the STP1 terminal) for 5 seconds or more
  2. When the stop light control (BRK-LP) relay drive output (STPO) is OFF, the relay contact remains closed (signal at the STP1 terminal is different from the input signal at the STP2) for 5 seconds or more
  3. When the stop light control (BRK-LP) relay drive output (STPO) is OFF, and the stop light switch ON, the stop light switch monitor (STP2) is OFF for 5 seconds or more
  • Stop light switch
  • Stop light switch circuit
  • Stop light control (BRK-LP) relay
  • Stop light control (BRK-LP) relay circuit
  • Skid control ECU
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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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