DTC C1A41: Brake Request Value Mismatch between ENG / EHV and Driving Support ECU [08/2013 - ]: Procedure

WARNING: This page is about a different car, the 2014 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR DTCs (ABS/VSC/TRAC)

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

Turn the power switch off.

B → See step 8

A: Go to next step

CHECK FOR DTCs (HYBRID CONTROL)

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

Turn the power switch off.

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 [08/2013 - ] .
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 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

Turn the power switch off.

B → See step 4

A → See step 11

REPLACE DRIVING SUPPORT ECU ASSEMBLY
Refer to REMOVAL [08/2013 - ]

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 [08/2013 - ] .
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 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

Turn the power switch off.

B → See step 6

A → END

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY
Refer to REMOVAL [08/2013 - ]

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 [08/2013 - ] .
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 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

Turn the power switch off.

B → See step 10

A → END

GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM. Refer to DIAGNOSTIC TROUBLE CODE CHART [08/2013 - ]
GO TO HYBRID CONTROL SYSTEM. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2013 - ]
REPLACE POWER MANAGEMENT CONTROL ECU. Refer to REMOVAL [08/2013 - ]
USE SIMULATION METHOD TO CHECK. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2013 - ]