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DTC C1A41: Brake Request Value Mismatch between ENG / EHV and Driving Support ECU: Procedure

WARNING: This page is about a different variant/trim than selected.

CHECK FOR DTCs (ELECTRONICALLY CONTROLLED BRAKE SYSTEM)

Connect the Techstream to the DLC3.
Turn the power switch on (IG).
Turn the Techstream on.
Enter the following menus: Chassis / ABS/VSC/TRAC / Trouble Codes.

Check for DTCs.

Result

Result	Proceed to
DTC is not output	A
DTC is output	B

B → See step 8

A: Go to next step

CHECK FOR DTCs (HYBRID CONTROL SYSTEM)

Connect the Techstream to the DLC3.
Turn the power switch on (IG).
Turn the Techstream on.
Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

Check for DTCs.

Result

Result	Proceed to
DTC is not output	A
DTC is output	B

B → See step 9

A: Go to next step

CHECK FOR DTCs (DTC C1A41)

Connect the Techstream to the DLC3.
Turn the power switch on (IG).
Clear the DTCs. Refer to DTC CHECK / CLEAR .
Perform the following to make sure that the DTC detection conditions are met.
HINT:

If the detection conditions are not met, the malfunction cannot be detected.
1. Drive the vehicle at a speed for which radar cruise control operation is possible.
2. Turn the cruise control system on using the cruise control switch (ON-OFF button).
3. Push the cruise control switch to -/SET to begin control of vehicle speed using the cruise control system.
Enter the following menus: Powertrain / Radar Cruise / Trouble Codes.

Check for DTCs.

Result

Result	Proceed to
DTC is not output	A
DTC C1A41 is output	B

B → See step 4

A → See step 11

REPLACE DRIVING SUPPORT ECU ASSEMBLY
1. Replace the driving support ECU assembly. Refer to REMOVAL .
NEXT: Go to next step

CHECK FOR DTCs (DTC C1A41)

Connect the Techstream to the DLC3.
Turn the power switch on (IG).
Clear the DTCs. Refer to DTC CHECK / CLEAR .
Perform the following to make sure that the DTC detection conditions are met.
HINT:

If the detection conditions are not met, the malfunction cannot be detected.
1. Drive the vehicle at a speed for which radar cruise control operation is possible.
2. Turn the cruise control system on using the cruise control switch (ON-OFF button).
3. Push the cruise control switch to -/SET to begin control of vehicle speed using the cruise control system.
Enter the following menus: Powertrain / Radar Cruise / Trouble Codes.

Check for DTCs.

Result

Result	Proceed to
DTC is not output	A
DTC C1A41 is output	B

B → See step 6

A → END

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY
1. Replace the brake booster with master cylinder assembly (skid control ECU). Refer to REMOVAL .
NEXT: Go to next step

CHECK FOR DTCs (DTC C1A41)

Connect the Techstream to the DLC3.
Turn the power switch on (IG).
Clear the DTCs. Refer to DTC CHECK / CLEAR .
Perform the following to make sure that the DTC detection conditions are met.
HINT:

If the detection conditions are not met, the malfunction cannot be detected.
1. Drive the vehicle at a speed for which radar cruise control operation is possible.
2. Turn the cruise control system on using the cruise control switch (ON-OFF button).
3. Push the cruise control switch to -/SET to begin control of vehicle speed using the cruise control system.
Enter the following menus: Powertrain / Radar Cruise / Trouble Codes.

Check for DTCs.

Result

Result	Proceed to
DTC is not output	A
DTC C1A41 is output	B

B → See step 10

A → END

GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM. Refer to HOW TO PROCEED WITH TROUBLESHOOTING
GO TO HYBRID CONTROL SYSTEM. Refer to HOW TO PROCEED WITH TROUBLESHOOTING
REPLACE POWER MANAGEMENT CONTROL ECU. Refer to REMOVAL
USE SIMULATION METHOD TO CHECK. Refer to HOW TO PROCEED WITH TROUBLESHOOTING