Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: ENG / EHV Device (C1A40)

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Audio & Visual & Telematics / Park Assist / Monitoring / Intelligent Clearance Sonar System / ENG / EHV Device (C1A40)

DESCRIPTION

When an EFI system malfunction signal sent by the ECM is detected by the clearance warning ECU assembly, DTC C1A40 is stored.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

C1A40

ENG / EHV Device

When the engine switch is on (IG), an EFI system malfunction signal is detected for 1 second or more.
  • EFI system
  • Clearance warning ECU assembly

CAUTION / NOTICE / HINT

NOTICE:

  • After turning the engine switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore make sure to read the disconnecting the cable from the negative (-) 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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PROCEDURE

1.

CHECK DTC OUTPUT

(a) Using the Techstream, check for DTCs according to the prompts on the screen.

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HINT:

After turning the engine 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.

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Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Clear DTCs

(c) Recheck for DTCs.

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Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Trouble Codes

HINT:

  • DTC C1A40 is stored when a malfunction signal sent from the EFI system is detected.
  • If the malfunctioning part has been repaired or replaced before rechecking for DTCs, DTC C1A40 will not be output again.
  • If DTC C1A40 is output frequently, duplicate the conditions that cause the problem symptoms and perform the inspection again, even though the DTC was not output when rechecking for DTCs.

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Result

Proceed to

DTC C1A40 is output

A

DTC C1A40 is not output

B
A

GO TO EFI SYSTEM

B

USE SIMULATION METHOD TO CHECK

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