System Readiness Tests status - which OBD II mode?

[turbo_bu]

Looking for some help in understanding the System Readiness Tests status screen (Shift + F5 in EFILive Scan) and where it gets its information from. From what I understand, the Ready or Not Ready status is stored in memory on the PCM and gets read when an OBD II command requests it.

What I am unsure of is which mode is being used to request the SRT status? Is it mode 19? I believe that mode 19 is DTC status, but maybe it is also used to evaluate the SRT status?

This brings me to another similar question regarding the Specifically monitored system test results (Shift + F6 in EFILive Scan). I believe that these are what feeds into the SRT status, but I am not sure which mode is used to check on them.

[joecar]

System Readiness Tests: aren't the Readiness/Continuous Monitors read by Mode $1...?

Specifically Monitored Tests: aren't these read by Mode $6...?


I quickly googled this: using-9-modes-global-obdii-diagnostics (http://www.searchautoparts.com/motorage/technicians/drivability/using-9-modes-global-obdii-diagnostics)

[turbo_bu]

Thanks for the link. It seems that those might be what I am looking for, I will have to do a little more digging.

[turbo_bu]

One follow up question about Mode 1 - when you ask for Mode 1, does it spit out all the System Readiness Test results, or do you have to ask it to spit out each one individually? It looks like that Mode is also used for general PID queries too??? So maybe you have to send it a string of commands in order to build up the Readiness test results?

[joecar]

Yes, mode 1 is used for both SRT's and pids...

I know that you have to ask mode 1 for specific pids... and I'm not sure, but I think you have to ask it for SRT's.