System Readiness Test (SRT) code is specified in Mode 1 of SAE J1979.

As part of an enhanced emissions test for Inspection & Maintenance (I/M), certain states require the status of SRT be used to indicate whether the ECM has completed self-diagnosis of major emission systems and components. Completion must be verified in order for the emissions inspection to proceed.

If a vehicle is rejected for a State emissions inspection due to one or more SRT items indicating "INCMP", use the information provided here to set the SRT to "CMPLT".

In most cases the ECM will automatically complete its self-diagnosis cycle during normal usage, and the SRT status will indicate "CMPLT" for each application system. Once set as "CMPLT", the SRT status remains "CMPLT" until the self-diagnosis memory is erased.

Occasionally certain portions of the self-diagnostic test may not be completed as a result of the customer's normal driving pattern; the SRT will indicate "INCMP" for these items.

NOTE: The SRT will also indicate "INCMP" if the self-diagnosis memory is erased for any reason or if the ECM memory power supply is interrupted for several hours.

If, during the state emissions inspection, the SRT indicates "CMPLT" for all test items, the inspector will continue with the emissions test. However, if the SRT indicates "INCMP" for one or more of the SRT items the vehicle is returned to the customer untested.

NOTE: If MIL is "ON" during the state emissions inspection, the vehicle is also returned to the customer untested even though the SRT indicates "CMPLT" for all test items. Therefore, it is important to check SRT ("CMPLT") and DTC (No DTCs) before the inspection.

SRT Item











SRT Set Timing
SRT is set as "CMPLT" after self-diagnosis has been performed one or more times. Completion of SRT is done regardless of whether the result is OK or NG. The set timing is different between OK and NG results and is shown in the table.

When all SRT related self-diagnoses showed OK results in a single cycle (Ignition OFF-ON-OFF), the SRT will indicate "CMPLT". -> Case 1 above

When all SRT related self-diagnoses showed OK results through several different cycles, the SRT will indicate "CMPLT" at the time the respective self-diagnoses have at least one OK result. -> Case 2 above

If one or more SRT related self-diagnoses showed NG results in 2 consecutive cycles, the SRT will also indicate "CMPLT". -> Case 3 above

The table above shows that the minimum number of cycles for setting SRT as "INCMP" is one (1) for each self-diagnosis (Case 1 & 2) or two (2) for one of self-diagnoses (Case 3). However, in preparation for the state emissions inspection, it is unnecessary of each self-diagnosis to be executed twice (Case 3) for the following reasons:


The SRT will indicate "CMPLT" at the time the respective self-diagnoses have one (1) OK result.
The emissions inspection requires "CMPLT" of the SRT only with OK self-diagnosis results.
When, during SRT driving pattern, 1st trip DTC (NG) is detected prior to "CMPLT" of SRT, the self-diagnosis memory must be erased from ECM after repair.
If the 1st trip DTC is erased, all the SRT will indicate "INCMP".
NOTE: SRT can be set as "CMPLT" together with the DTC(s). Therefore, DTC check must always be carried out prior to the state emission inspection even though the SRT indicates "CMPLT".






SRT Service Procedure
If a vehicle has failed the state emissions inspection due to one or more SRT items indicating "INCMP", review the flowchart diagnostic sequence.






How to Display SRT Code

With CONSULT-II
Selecting "SRT STATUS" in "DTC CONFIRMATION" mode with CONSULT-II.

For items whose SRT codes are set, a "CMPLT" is displayed on the CONSULT-II screen; for items whose SRT codes are not set, "INCMP" is displayed.

With GST
Selecting Mode 1 with GST (Generic Scan Tool)

A sample of CONSULT-II display for SRT code is as shown.
"INCMP" means the self-diagnosis is incomplete and SRT is not set. "CMPLT" means the self-diagnosis is complete and SRT is set.

How to Set SRT Code
To set all SRT codes, self-diagnosis for the items indicated above must be performed one or more times. Each diagnosis may require a long period of actual driving under various conditions.

With CONSULT-II
Perform corresponding DTC Confirmation Procedure one by one based on "Performance Priority".

Without CONSULT-II
The most efficient driving pattern in which SRT codes can be properly set is explained in Driving Patterns 1, 2, 3 & 4. The driving pattern should be performed one or more times to set all SRT codes.

The time required for each diagnosis varies with road surface conditions, weather, altitude, individual driving habits, etc.
Zone A refers to the range where the time required, for the diagnosis under normal conditions*, is the shortest.

Zone B refers to the range where the diagnosis can still be performed if the diagnosis is not completed within zone A.

*: Normal conditions refer to the following:


Sea level
Flat road
Ambient air temperature: 20 - 30 °C (68 - 86 °F)
Diagnosis is performed as quickly as possible under normal conditions. Under different conditions [For example: ambient air temperature other than 20 - 30 °C (68 - 86 °F) ], diagnosis may also be performed.
Pattern 1:


The engine is started at the engine coolant temperature of -10 to 35 °C (14 to 95 °F) (where the voltage between the ECM terminal 93 and ground is 3.0 - 4.3 V ).
The engine must be operated at idle speed until the engine coolant temperature is greater than 70 °C (158 °F) (where the voltage between the ECM terminal 93 and ground is lower than 1.4 V ).
The engine is started at the fuel tank temperature of warmer than 0 °C (32 °F) (where the voltage between the ECM terminal 75 and ground is less than 4.1 V ).
Pattern 2:


When steady-state driving is performed again even after it is interrupted, each diagnosis can be conducted. In this case, the time required for diagnosis may be extended.
Pattern 3:


The driving pattern outlined in *2 must be repeated at least 3 times.
Pattern 4:


Tests are performed after the engine has been operated for at least 17 minutes .
The accelerator pedal must be held very steady during steady-state driving.
If the accelerator pedal is moved, the test must be conducted all over again.
*1: Depress the accelerator pedal until vehicle speed is 90 KPH (56 MPH) , then release the accelerator pedal and keep it released for more than 10 seconds . Depress the accelerator pedal until vehicle speed is 90 KPH (56 MPH) again.

*2: Operate the vehicle in the following driving pattern.


Decelerate vehicle to 0 KPH (0 MPH) and let engine idle.
Repeat driving pattern shown at least 10 times.
During acceleration, hold the accelerator pedal as steady as possible.





*3: Checking the vehicle speed with GST is advised.

Suggested Transmission Gear Position for A/T Models
Set the selector lever in the "D" position with the overdrive switch turned ON.






Suggested upshift speeds for M/T models
Shown are suggested vehicle speeds for shifting into a higher gear. These suggestions relate to fuel economy and vehicle performance. Actual upshift speeds will vary according to road conditions, the weather and individual driving habits.






Suggested Maximum Speed in Each Gear
Downshift to a lower gear if the engine is not running smoothly, or if you need to accelerate.

Do not exceed the maximum suggested speed (shown) in any gear. For level road driving, use the highest gear suggested for that speed. Always observe posted speed limits and drive according to the road conditions to ensure safe operation. Do not over-rev the engine when shifting to a lower gear as it may cause engine damage or loss of vehicle control.