Brake Control

BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: C1241: Low Power Supply Voltage Malfunction
C1241 - Low Power Supply Voltage Malfunction

DESCRIPTION

If a malfunction is detected in the power supply circuit, the skid control ECU (housed in the actuator assembly) stores this DTC and the fail-safe function prohibits ABS/TRAC/VSC operation.

This DTC is stored when the IG1 terminal voltage deviates from the DTC detection condition due to a malfunction in the power supply or charging circuit such as the battery or alternator circuit, etc.

The DTC is canceled when the IG1 terminal voltage returns to normal.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
* Inspect the fuses for circuits related to this system before performing the following inspection procedure.
* When replacing the brake actuator assembly, perform zero point calibration Component Tests and General Diagnostics.

PROCEDURE

1. CHECK BATTERY

(a) Check the battery voltage.

Standard voltage:

11 to 14 V

Result:





C -- CHECK OR REPLACE CHARGING SYSTEM OR BATTERY Testing and Inspection

B -- CHECK OR REPLACE CHARGING SYSTEM OR BATTERY Testing and Inspection
A -- Continue to next step.

2. INSPECT SKID CONTROL ECU (IG1 TERMINAL)

(a) Make sure that there is no looseness in the locking part and connecting part of the connectors.





(b) Disconnect the skid control ECU connector.

(c) Turn the ignition switch to ON.

(d) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)
OK -- Continue to next step.

3. INSPECT SKID CONTROL ECU (GND1 TERMINAL)

(a) Turn the ignition switch off.





(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (GND1 CIRCUIT)
OK -- Continue to next step.

4. RECONFIRM DTC

(a) Reconnect the skid control ECU connector.

(b) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.

(c) Start the engine.

(d) Drive the vehicle at a speed of 20 km/h (12 mph) or more for 30 seconds or more.

(e) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.

Result:





HINT
If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step Problem Symptoms Table.

B -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal

A -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) How To Proceed With Troubleshooting