Anti-Lock Brake System (for Sedan)

BRAKE CONTROL: ANTI-LOCK BRAKE SYSTEM (for Sedan): C1241/41: Low Battery Positive Voltage or Abnormally High Battery Positive Voltage

DTC C1241/41 - Low Battery Positive Voltage or Abnormally High Battery Positive Voltage

DESCRIPTION

When there is an abnormality in the power supply circuit of the brake actuator (skid control ECU), the skid control ECU sets a DTC and the operation is prohibited by the fail-safe function. This DTC is set when the voltage supplied to terminal IG1 is outside the DTC detection threshold, due to abnormalities in the battery, power source circuits or charging circuits such as the alternator circuit.
The fail-safe function is canceled when the voltage to terminal IG1 returns to normal.






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK SKID CONTROL ECU TERMINAL VOLTAGE




(a) Disconnect the skid control ECU connector.
(b) Turn the ignition switch to ON.
(c) Measure the voltage.
Standard voltage:






NG -- INSPECT FUSES (ECU-IG, AM1)
OK -- Continue to next step.
2. RECONFIRM DTC
(a) Clear the DTC ABS (Antilock Brake System) (for Sedan).
(b) Drive the vehicle at 2 mph (3 km/h) or more for several seconds.
(c) Check if the same DTC is output ABS (Antilock Brake System) (for Sedan).
Result:






B -- END
A -- REPLACE BRAKE ACTUATOR
3. INSPECT FUSES (ECU-IG, AM1)




(a) Remove the ECU-IG fuse and AM1 fuse from the main body ECU.
(b) Measure the resistance.
Standard resistance:
Below 1 Ohms
NG -- CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE
OK -- Continue to next step.
4. INSPECT BATTERY
(a) Check the battery voltage.
Standard voltage:
11 to 14 V
NG -- CHECK CHARGING SYSTEM
OK -- Continue to next step.
5. INSPECT IGNITION RELAY NO. 1




(a) Remove the IG1 relay from the main body ECU.




(b) Measure the resistance.
Standard resistance:






NG -- REPLACE IGNITION RELAY NO. 1
OK -- Continue to next step.
6. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BODY GROUND)




(a) Disconnect the skid control ECU connector.
(b) Measure the resistance.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE BRAKE ACTUATOR