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:
Installation
1. INSTALL RACK & PINION POWER STEERING GEAR ASSEMBLY
(a) Install the power steering gear assembly with the 2
bolts and nuts.
Torque: 70 N*m (714 kgf*cm, 52 ft.*lbf)
2. CONNECT PRESSURE FEED TUBE ASSEMBLY
(a) Connect the pressure feed tube assembly to the
power steering gear asse ...
Problem symptoms table
HINT:
Inspect the "Fuse" and "Relay" before confirming the
suspected area as shown in the table below.
DISPLAY FUNCTION:
SOUND FUNCTION:
REMOTE CONTROL FUNCTION:
*1: without Navigation System
*2: with Navigation System ...
How to proceed with
troubleshooting
HINT:
Use these procedures to troubleshoot the power door lock
control system.
The intelligent tester should be used in steps 4 and 5.
1 VEHICLE BROUGHT TO WORKSHOP
2 CUSTOMER PROBLEM ANALYSIS CHECK
HINT:
In troubleshooting, confirm that the problem symptoms
have ...
