Toyota Sienna Service Manual: Master Cylinder Pressure Sensor Malfunction
DTC C1246/46 Master Cylinder Pressure Sensor Malfunction
DESCRIPTION
Master cylinder pressure sensor is connected to the skid control ECU in the actuator.
INSPECTION PROCEDURE
1 READ VALUE ON INTELLIGENT TESTER (MASTER CYLINDER PRESSURE SENSOR)
(a) Connect the intelligent tester to the DLC3.
(b) Start the engine.
(c) Select the DATA LIST mode on the intelligent tester.
ABS / VSC: 
(d) Check that the brake fluid pressure value of the master cylinder pressure sensor indicated on the intelligent tester, changes when the brake pedal is depressed.
OK: Brake fluid pressure value should change.
NOTICE: When replacing the brake actuator assembly, perform zero point calibration (See page BC-70).
REPLACE BRAKE ACTUATOR ASSEMBLY
2 INSPECT SKID CONTROL ECU (STP1 TERMINAL)
(a) Disconnect the skid control ECU connector.
(b) Measure the voltage according to the value(s) in the table below
Standard voltage
NOTICE: When replacing the brake actuator assembly, perform zero point calibration (See page BC-70).
REPLACE BRAKE ACTUATOR ASSEMBLY
Low Battery Positive Voltage
DTC C1241/41 Low Battery Positive Voltage
DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT ECU-IG FUSE
(a) Remove the ECU-IG fuse from the driver side J/B.
(b) Check continu ...
Open in Stop Light Switch Circuit
DTC C1249/49 Open in Stop Light Switch Circuit
DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK STOP LIGHT SWITCH OPERATION
(a) Check that the stop light comes on when the brak ...
Other materials:
Enter test mode
HINT:
Operation of the tire pressure warning reset switch
can be checked in TEST MODE.
During TEST MODE, the system is not initialized by
pushing the tire pressure warning reset switch. The
circuit of the tire pressure warning reset switch can be
inspected during this mode.
(a) Make ...
Installation
HINT:
Install the RH side by the same procedure as the LH side.
1. INSTALL FRONT DISC BRAKE CYLINDER SLIDE BUSH
(a) Apply the lithium soap base glycol grease to a new
front disc brake cylinder slide bush.
(b) Install the cylinder slide bush to the bottom side of
the front disc brake cyli ...
How to proceed with troubleshooting
HINT:
Use the following procedures to troubleshoot the tire
pressure warning system.
*: Use the intelligent tester.
1 VEHICLE BROUGHT TO WORKSHOP
2 CUSTOMER PROBLEM ANALYSIS
(a) Interview the customer to confirm the trouble.
HINT:
It is important to collect as much specific informat ...
