DTC C1242: Open Circuit in IG1/IG2 Power Source Circuit [10/2018 - ]: Procedure
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- CHECK FREEZE FRAME DATA
- Check the INF code from the Freeze Frame Data stored when DTC (C1242) was stored.
Refer to FREEZE FRAME DATA [10/2018 - ]
Chassis > ABS/VSC/TRAC > Trouble Codes
Result
Result Proceed to INF code 111 is output. A INF code 112 is output. B
Result:
B
REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY. Refer to REMOVAL [10/2018 - 07/2022] , or refer to REMOVAL [07/2022 - ]
Result:
A
See step 2
- Check the INF code from the Freeze Frame Data stored when DTC (C1242) was stored.
- CHECK HARNESS AND CONNECTOR (IG1 AND IG2 TERMINAL)
- Turn the power switch off.
*a Front view of wire harness connector
(to Skid Control ECU (Brake Booster with Master Cylinder Assembly)) - Make sure that there is no looseness at the locking part and the connecting part of the connector.
OK
The connector is securely connected.
- Disconnect the A37 skid control ECU (brake booster with master cylinder assembly) connector.
- Check both the connector case and the terminals for deformation and corrosion.
OK
No deformation or corrosion.
- Turn the power switch on (IG).
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Switch Condition Specified Condition A37-23 (IG1) - Body ground Power switch on (IG) 11 to 14 V A37-9 (IG2) - Body ground Power switch on (IG) 11 to 14 V Result
Result Proceed to 11 to 14 V. A Below 11 V. B
Result:
A
REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY. Refer to REMOVAL [10/2018 - 07/2022] , or refer to REMOVAL [07/2022 - ]
Result:
B
REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 AND/OR IG2 CIRCUIT)
- Turn the power switch off.