C1242

BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: C1242/42: IG2 Power Source Circuit

DTC C1242/42 - IG2 Power Source Circuit

DESCRIPTION

If there is a problem with the master cylinder solenoid power supply circuit, the skid control ECU outputs DTCs and prohibits operation under the fail-safe function.
If the voltage supplied to the IG2 terminal is not within the standard due to malfunctions in areas such as the battery or alternator circuit, this DTC is stored.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTE: When replacing the master cylinder solenoid, perform zero point calibration Programming and Relearning.

PROCEDURE

1. INSPECT BATTERY
(a) Check the battery voltage.
Standard voltage:
11 to 14 V

NG -- INSPECT CHARGING SYSTEM
OK -- Continue to next step.

2. INSPECT IGN FUSE
(a) Remove the IGN fuse from the driver side junction block.
(b) Check the IGN fuse.
Standard resistance:
Below 1 Ohms

NG -- REPLACE IGN FUSE
OK -- Continue to next step.

3. INSPECT SKID CONTROL ECU (IG2 TERMINAL)
(a) Install the IGN fuse.




(b) Disconnect the skid control ECU (S29) 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 (IG2 CIRCUIT)
OK -- Continue to next step.

4. INSPECT SKID CONTROL ECU (GND TERMINAL)




(a) Disconnect the skid control ECU (S28) connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:





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

5. RECONFIRM DTC
(a) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
(b) Check if the same DTC is detected Reading and Clearing Diagnostic Trouble Codes.

HINT: Reinstall the sensors, connectors, etc. and restore the previous vehicle conditions before rechecking for DTCs.

Result:





B -- CHECK FOR INTERMITTENT PROBLEMS
A -- REPLACE MASTER CYLINDER SOLENOID