Toyota Sienna Service Manual: Open in Stop Light Switch Circuit
DTC C1249/49 Open in Stop Light Switch Circuit
DESCRIPTION
This skid control ECU inputs the stop light switch signal and detects the status of brake operation.
The skid control ECU has an open detection circuit. If an open in the stop light switch input line or GND side stop light circuit is detected when the stop light switch is off, this DTC is output.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK STOP LIGHT SWITCH OPERATION
(a) Check that the stop light comes on when the brake pedal is depressed, and goes off when the brake pedal is released.
OK: Stop light switch function is normal.
HINT: Check the stop light bulb as it may have burnt out.
2 INSPECT SKID CONTROL ECU (STP TERMINAL VOLTAGE)
(a) Disconnect the skid control ECU connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage 
Result 
3 RECONFIRM DTC
(a) Clear the DTC (See page BC-10).
(b) Check that the same DTC is recorded (See page BC- 10).
HINT: Reinstall the sensors, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.
Result
REPLACE BRAKE ACTUATOR ASSEMBLY
4 INSPECT STOP LIGHT SWITCH (POWER SOURCE TERMINAL VOLTAGE)
(a) Disconnect the stop light switch connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage 
5 INSPECT STOP LIGHT SWITCH
(a) Measure the resistance according to the value(s) in the table below.
Standard resistance
6 CHECK HARNESS AND CONNECTOR (BETWEEN SKID CONTROL ECU AND STOP LIGHT SWITCH)
(a) Disconnect the skid control ECU connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance
HINT:
- When troubleshooting in accordance with the DTC CHART, check DTCs before replacing the brake actuator assembly (See page BC-10).
- When troubleshooting in accordance with the PROBLEM SYMPTOMS TABLE, be sure to follow the table before replacing the brake actuator assembly (See page BC-7).
REPLACE BRAKE ACTUATOR ASSEMBLY
Low Battery Positive Voltage
DTC C1241/41 Low Battery Positive Voltage
DESCRIPTION
If there is a problem with the brake actuator assembly (skid control ECU)
power supply circuit, the skid
control ECU outputs the DTC and proh ...
Open in Pump Motor Circuit
DTC C1251/51 Open in Pump Motor Circuit
DESCRIPTION
The motor relay (semiconductor relay) is housed in the brake actuator
assembly and drives the pump
motor based on a signal from the skid contro ...
Other materials:
Hydraulic test
1. Perform hydraulic test
(a) Measure the line pressure.
NOTICE:
Perform the test at the normal operating ATF
(Automatic Transmission Fluid) temperature:
50 to 80°C (122 to 176°F).
The line pressure test should always be
carried out in pairs. One technician should
...
Oxygen (A/F) Sensor Signal Stuck
DTC P2195 Oxygen (A/F) Sensor Signal Stuck Lean (Bank 1
Sensor 1)
DTC P2196 Oxygen (A/F) Sensor Signal Stuck Rich (Bank 1
Sensor 1)
DTC P2197 Oxygen (A/F) Sensor Signal Stuck Lean (Bank 2
Sensor 1)
DTC P2198 Oxygen (A/F) Sensor Signal Stuck Rich (Bank 2
Sensor 1)
HINT:
Although the ...
Back Sonar Sensor LH Circuit
DESCRIPTION
An ultrasonic sensor consists of a sensor portion that transmits and receives
ultrasonic waves and a preamplifier
that amplifies them. The ultrasonic sensor outputs the ultrasonic waves and
sends the received
signals to the clearance warning ECU.
WIRING DIAGRAM
INSPECTION PR ...
