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:
Cold Start Ignition Timing Performance
DESCRIPTION
This monitor will run when the engine is started at -10 to 50°C (14 to 122°F)
of the engine coolant
temperature. The DTC will set after the engine idling for 13 seconds (2 trip
detection logic).
The DTC is designed to monitor the idle air control at cold start. When the
...
Installation
1. INSTALL STABILIZER BAR FRONT
2. INSTALL FRONT STABILIZER BAR BUSH NO.1
(a) Install the front stabilizer bar bush No. 1.
HINT:
Install the bushing to the outer side of the bushing
stopper on the stabilizer bar as shown in the
illustration.
4. INSTALL RACK & PINION POWER STEERING GEA ...
Front Occupant Classification Sensor RH Collision
Detection
DTC B1786 Front Occupant Classification Sensor RH Collision
Detection
DESCRIPTION
DTC B1786 is output when the occupant classification ECU receives a collision
detection signal sent by
the front occupant classification sensor RH if an accident occurs.
DTC B1786 is also output when the front ...