Toyota Sienna Service Manual: Control Module Performance
DESCRIPTION
The ECM continuously monitors its main and sub CPUs. This self-check ensures that the ECM is functioning properly. If outputs from the CPUs are different and deviate from the standards, the ECM will illuminate the MIL and set a DTC immediately.
The ECM also monitors the cruise control cancel circuit. If this circuit malfunctions, the ECM will set a DTC immediately (MIL is not illuminated).
| NOTICE: First check for an exhaust gas leak around the HO2S if P0606 is present. An exhaust gas leak generates noise in the HO2S output. The ECM may interpret this as an HO2S transistor malfunction. |
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
INSPECTION PROCEDURE
1 CHECK WHETHER DTC OUTPUT RECURS (IN ADDITION TO DTC P0607)
(a) Connect the intelligent tester to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Turn the tester on.
(d) Clear the DTC.
(e) Turn the ignition switch off.
(f) Disconnect the battery negative terminal and wait for 1 minute.
(g) Connect the battery negative terminal.
(h) Turn the ignition switch to the ON position.
(i) Enter the following menus: DIAGNOSIS / ENHANCED II / DTC INFO / CURRENT CODES.
(j) Read the DTCs.
Result 
REPLACE ECM
ECM / PCM Processor
DESCRIPTION
The ECM continuously monitors its internal processors (CPUs), A/F sensor
transistors and heated oxygen
sensor (HO2S) transistors. This self-check ensures that the ECM is functionin ...
Starter Relay Circuit High
MONITOR DESCRIPTION
While the engine is being cranked, the positive battery voltage is applied to
terminal STA of the ECM.
If the ECM detects the Starter Control (STA) signal while the vehic ...
Other materials:
Unlock Warning Switch Circuit
DESCRIPTION
The unlock warning switch detects if the key is in the ignition key cylinder.
The unlock warning switch turns on when the key is inserted into the ignition
key cylinder and turns off
when the key is removed from the cylinder.
The body ECU is connected to the unlock warning swit ...
Suspension system
How to proceed with troubleshooting
HINT:
This is the repair procedure for vehicle pull.
Problem symptoms table
FRONT SUSPENSION SYSTEM
REAR SUSPENSION SYSTEM
...
Taking out the jack and tools
Remove the cover.
Remove the adapter socket.
Remove the jack.
Remove the wheel nut wrench.
...