Toyota Sienna Service Manual: Internal Control Module Random Access Memory (RAM) Error
DTC P0604 Internal Control Module Random Access Memory (RAM) Error
DESCRIPTION
The ECM continuously monitors its own internal memory status, internal circuits, and output signals transmitted to the throttle actuator. This self-check ensures that the ECM is functioning properly. If any malfunction is detected, the ECM sets the appropriate DTC and illuminates the MIL.
The ECM memory status is diagnosed by internal mirroring of the main CPU and the sub CPU to detect Random Access Memory (RAM) errors. The two CPUs also perform continuous mutual monitoring. The ECM illuminates the MIL and sets a DTC if: 1) outputs from the two CPUs are different or deviate from the standards, 2) the signals sent to the throttle actuator deviate from the standards, 3) a malfunction is found in the throttle actuator supply voltage, and 4) any other ECM malfunction is found.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
ECM RAM errors:
INSPECTION PROCEDURE
Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
1 CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0604)
- Connect the intelligent tester to the DLC3.
- Turn the ignition switch to the ON position.
- Turn the tester on.
- Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.
- Read DTCs.
Result
REPLACE ECM
System Voltage
DTC P0560 System Voltage
MONITOR DESCRIPTION
The battery supplies electricity to the ECM even when the ignition switch is
off. This power allows the
ECM to store data such as DTC history, freeze ...
ECM / PCM Processor
DTC P0606 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 ...
Other materials:
Master cylinder pressure sensor check (when using sst check wire)
(a) Leave the vehicle in a stationary condition and
release the brake pedal for 1 second or more, and
quickly depress the brake pedal with a force of 98 N
(10 kgf, 22 lbf) or more for 1 second or more.
(b) Check the ABS warning light stays on for 3
seconds.
HINT:
At this time, the ABS wa ...
Installation
1. INSTALL REAR SEAT 3 POINT TYPE BELT
ASSEMBLY (for 8-Passenger)
HINT: Refer to the instructions for reassembly of the rear
No. 1 seat assembly (for center seat).
Install the rear seat 3 point type belt assembly with
the bolt.
Torque: 42 N*m (430 kgf*cm, 31 ft.*lbf)
2. INSTALL ...
Inspection procedure
1 BASIC INSPECTION
Conditions necessary for the power slide door to open:
Power slide door main switch is in the ON position
(switch free: orange paint on the top of the switch
appears).
Slide door is unlocked (door lock position switch is
in the ON position when the slide do ...
