Toyota Sienna Service Manual: Engine Control System Malfunction
DTC C1201/51 Engine Control System Malfunction
DESCRIPTION
If trouble occurs the engine control system, the ECM transmits the abnormality to the skid control ECU.
The skid control ECU set this DTC and the skid control ECU prohibits TRAC and
VSC control. 
INSPECTION PROCEDURE
1 CHECK ENGINE CONTROL SYSTEM
(a) Check if the normal system code is recorded for engine control system.
Result 
REPLACE ECM
Open or Short Circuit in ABS Solenoid Relay Circuit
DESCRIPTION
The ABS solenoid relay is built in the brake actuator assembly. This relay
supplies power to each ABS
solenoid. If the initial check is OK, after the ignition switch is turned to t ...
ECM Communication Circuit Malfunction
DTC C1203/53 ECM Communication Circuit Malfunction
DESCRIPTION
The circuit is used to send TRAC and VSC control information from the skid
control ECU to the ECM, and
engine control information fr ...
Other materials:
Inspection and adjustment procedure
Tire valve
Tire pressure gauge
Remove the tire valve cap.
Press the tip of the tire pressure gauge onto the tire valve.
Read the pressure using the gauge gradations.
If the tire inflation pressure is not at the recommended level, adjust
the pressure.
If you add too much air, ...
U151f automatic transaxle
Service data
TORQUE SPECIFICATIONS
...
Rear Air Mix Damper Control Servo Motor Circuit
DESCRIPTION
The rear air mix control servo motor (water valve servo motor) is controlled
by the A/C amplifier.
The rear air mix control servo motor moves the air mix damper by rotating
(normal, reverse) with electrical
power from the A/C amplifier.
WIRING DIAGRAM
INSPECTION PROCEDURE
...
