Lexus ES: Stop Light Relay Circuit (C1A4B)
DESCRIPTION
When a stop light relay circuit malfunction signal sent from the electronically controlled brake system is detected by the clearance warning ECU assembly, DTC C1A4B is stored.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area |
|---|---|---|---|
| C1A4B | Stop Light Relay Circuit | Stop light relay circuit malfunction | Electronically controlled brake system |
CAUTION / NOTICE / HINT
NOTICE:
-
After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.
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After replacing an ultrasonic sensor or the clearance warning ECU assembly, perform the necessary procedures (adjustment, calibration, initialization or registration).
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When DTC C1A4B is stored, there may be a malfunction in the lighting system. Inspect the lighting system before performing the following procedure.
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PROCEDURE
| 1. | CHECK DTC OUTPUT |
(a) Using the Techstream, check for DTCs according to the prompts on the screen.
HINT:
After turning the power switch from off to on (IG), wait 4 seconds or more before checking for DTCs.
Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Trouble Codes(b) Clear the DTCs according to the screen on the Techstream.
Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Clear DTCs(c) Recheck for DTCs.
Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Trouble CodesHINT:
- DTC C1A4B is stored when a malfunction signal sent from the electronically controlled brake system is detected.
- If the malfunctioning part has been repaired or replaced before rechecking for DTCs, DTC C1A4B will not be output again.
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If DTC C1A4B is output frequently, duplicate the conditions that cause the problem symptoms and perform troubleshooting again, even though the DTC was not output when rechecking for DTCs.
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| Result | Proceed to |
|---|---|
| DTC C1A4B is output | A |
| DTC C1A4B is not output | B |
| A | .gif) | GO TO PRE-COLLISION SYSTEM |
| B | | USE SIMULATION METHOD TO CHECK |
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ENG / EHV Device (C1A40)
DESCRIPTION When a SFI system malfunction signal sent by the hybrid vehicle control ECU is detected by the clearance warning ECU assembly, DTC C1A40 is stored. DTC No. Detection Item DTC Detect
ENG / EHV Device (C1A40)
DESCRIPTION When a SFI system malfunction signal sent by the hybrid vehicle control ECU is detected by the clearance warning ECU assembly, DTC C1A40 is stored. DTC No. Detection Item DTC Detect
Brake System (C1A50)
DESCRIPTION When an electronically controlled brake system malfunction signal sent from the skid control ECU is detected by the clearance warning ECU assembly, DTC C1A50 is stored. DTC No. Detect
SEE MORE:
Removal
REMOVAL PROCEDURE 1. REMOVE FRONT DOOR SCUFF PLATE LH Click here 2. REMOVE COWL SIDE TRIM BOARD LH Click here 3. REMOVE FRONT DOOR OPENING TRIM COVER LH Click here 4. REMOVE INSTRUMENT SIDE PANEL LH Click here 5. REMOVE NO. 1 INSTRUMENT PANEL UNDER COVER SUB-ASSEMBLY Click here 6. REM
Installation
INSTALLATION CAUTION / NOTICE / HINT HINT:
Use the same procedure for the RH side and LH side.
The following procedure is for the LH side.
PROCEDURE 1. PRECAUTION NOTICE: After turning the engine switch (for Gasoline Model) or power switch (for HV Model) off, waiting time may be required bef
