MONITOR DESCRIPTION
The ECM continuously monitors its internal memory status. This self-check ensures that the ECM is functioning properly. It is diagnosed by internal "mirroring" of the main CPU and sub CPU to detect Random Access Memory (RAM) errors. If outputs from these CPUs are different and deviate from the standard, the ECM illuminates the MIL and stores the DTC immediately.
DTC No. |
DTC Detection Condition |
Trouble Area |
---|---|---|
P0604 |
ECM RAM error (1 trip detection logic) |
ECM |
MONITOR STRATEGY
Related DTCs |
P0604: ECM RAM Error |
Required Sensors/Components (Main) |
ECM |
Required Sensors/Components (Related) |
None |
Frequency of Operation |
Continuous |
Duration |
6 times |
MIL Operation |
Immediate |
Sequence of Operation |
None |
TYPICAL ENABLING CONDITIONS
Monitor runs whenever the following DTCs are not stored |
None |
TYPICAL MALFUNCTION THRESHOLDS
RAM mirror check |
Fail |
CONFIRMATION DRIVING PATTERN
HINT:
Techstream Display |
Description |
---|---|
NORMAL |
|
ABNORMAL |
|
INCOMPLETE |
|
N/A |
|
HINT:
HINT:
CAUTION / NOTICE / HINT
HINT:
Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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.
PROCEDURE
1. |
READ OUTPUT DTC (DTC P0604) |
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Clear the DTC (See page ).
(e) Turn the ignition switch off and turn the Techstream off.
(f) Disconnect the Techstream.
(g) Disconnect the cable from the negative (-) battery terminal and wait for 1 minute.
(h) Connect the cable to the negative (-) battery terminal.
(i) Connect the Techstream to the DLC3.
(j) Turn the ignition switch to ON.
(k) Turn the Techstream on.
(l) Wait 16 seconds or more.
(m) Enter the following menus: Powertrain / Engine / Trouble Codes.
(n) Read the DTCs.
Result |
Proceed to |
---|---|
DTC is not output |
A |
DTC P0604 is output |
B |
A | ![]() |
CHECK FOR INTERMITTENT PROBLEMS |
B | ![]() |
REPLACE ECM |
Cold Start Ignition Timing Performance (P050B)
DESCRIPTION
This monitor will run when the engine is started at an engine coolant temperature
of -10 to 50°C (14 to 122°F). The DTC is stored after the engine idles for 13
seconds (2 trip detection logic).
The DTC is designed to monitor the ignition ti ...
Problem Symptoms Table
PROBLEM SYMPTOMS TABLE
Use the table below to help determine the cause of problem symptoms. If multiple
suspected areas are listed, the potential causes of the symptoms are listed in order
of probability in the "Suspected Area" column of the tab ...
Diagnosis System
DIAGNOSIS SYSTEM
1. DESCRIPTION
(a) Diagnostic System
When troubleshooting a vehicle with a diagnostic system, the only difference
from the usual troubleshooting procedure is connecting the Techstream to the vehicle
and reading various data output from ...