Last Modified: 4-30-2014 6.6 C Doc ID: RM000002KQO02EX
Model Year: 2006 Model: LX470 Prod Date Range: [05/2005 -           ]
Title: 2UZ-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0604; Random Access Memory (RAM); 2006 MY LX470 [05/2005 -        ]

DTC

P0604

Random Access Memory (RAM)

DESCRIPTION

The ECM continuously monitors its internal memory status. This self-check ensures that the ECM is functioning properly. This is diagnosed by internal "mirroring" of the main CPU and sub CPU to detect the Random Access Memory (RAM) errors. If outputs from these CPUs are different and deviate from the standard, the ECM will illuminate the MIL and set a DTC immediately.

DTC No.

DTC Detection Condition

Trouble Area

P0604

ECM RAM errors

ECM

MONITOR STRATEGY

Related DTCs

None

Required sensors / components (Main)

ECM

Required sensors / components (Related)

None

Frequency of operation

Continuous

Duration

16 seconds

MIL operation

Immediate

Sequence of operation

None

TYPICAL ENABLING CONDITIONS

None

-

TYPICAL MALFUNCTION THRESHOLDS

Main CPU and sub CPU mirroring

Fail

INSPECTION PROCEDURE

PROCEDURE

1.

CHECK DTC

(a) Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.

(b) Clear DTC 2006 MY LX470 [05/2005 -        ]; 2UZ-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: DTC CHECK / CLEAR .

(c) Turn the ignition switch OFF.

(d) Disconnect the cable from the negative battery terminal and wait for 1 minute.

(e) Connect the cable to the negative battery terminal.

(f) Turn the ignition switch ON.

(g) Check DTC.

OK:

P0604 is not present.

NG

REPLACE ECM

OK

CHECK FOR INTERMITTENT PROBLEMS