Originally Posted by merkzu

I'll try it after work. It would just be disabling the checks, not shutting off the heater correct?

Originally Posted by dexmix

I'll try this either tonight or tomorrow. I didn't realize scan-tech can check readiness codes? what tab is that on?

Originally Posted by mrfred

I've been trying to get at this heater check routine from a few different angles. Today, I think I found the periphery bit that controls the O2 heater check. It appears to be periphery2, bit 11. Not sure what effect it will have on the OBD-II test readiness state. Here's what to do:

Change Periphery2 from EFDF to E7DF

If I am interpretting the ROM code correctly, there is no way to disable just the rear O2 heater. This will disable both the front and rear O2 heater checks, so beware of that limitation. If someone could try this and report back to me, I would appreciate it. Also, could you use ScanTech to observe the "Readiness" condition for the heater check?

Originally Posted by merkzu

I took a little break from work. Changed Periphery2 to E7DF and went for a drive. Didn't get a CEL. That's what I care about, so it seems to be working? I'm going to leave my resistor disconnected

Here's scantech:


This is my xml for periphery2 on 88590015, just to make sure its correct..
<table name="ECU Periphery2" category="Misc" address="fca" type="1D" level="1" scaling="Hex16"/>

Originally Posted by dexmix

...sometimes it takes a while of driving around for them to complete. I'll try this out.

edit: shouldn't your address=0xFFFF6BB8 ??? or am i misunderstanding that the periphery bits get written to the chunk starting at FFFF6BB2

Originally Posted by mrfred

It could be the "drive it around" thing, but probably not. I think I can fix the readiness issue too. Just need more time to study things.

Yes, FFFF6BB8 is the RAM address where it is held when the car is running. But the value is read from FCA when the car is started, so FCA is the one to change.

Originally Posted by dexmix

my bad. the FFFF should have given away that its a RAM address.

Originally Posted by mrfred

For punishment, you need to learn the entire sh2 language so you don't make another mistake. ;-)

Originally Posted by mrfred

For punishment, you need to learn the entire sh2 language so you don't make another mistake. ;-)

Originally Posted by merkzu

I took a little break from work. Changed Periphery2 to E7DF and went for a drive. Didn't get a CEL. That's what I care about, so it seems to be working? I'm going to leave my resistor disconnected

Here's scantech:


This is my xml for periphery2 on 88590015, just to make sure its correct..
<table name="ECU Periphery2" category="Misc" address="fca" type="1D" level="1" scaling="Hex16"/>

Originally Posted by scheides

I tried this last night on an a friend's IX, worked perfect. Good work mrfred!

Originally Posted by mrfred

I've been trying to get at this heater check routine from a few different angles. Today, I think I found the periphery bit that controls the O2 heater check. It appears to be periphery2, bit 11. Not sure what effect it will have on the OBD-II test readiness state. Here's what to do:

Change Periphery2 from EFDF to E7DF

If I am interpretting the ROM code correctly, there is no way to disable just the rear O2 heater. This will disable both the front and rear O2 heater checks, so beware of that limitation. If someone could try this and report back to me, I would appreciate it. Also, could you use ScanTech to observe the "Readiness" condition for the heater check?

Originally Posted by alan678

Seems like Periphery2 for ROM ID 96940011 reads the same stock value as above (EFDF) I changed mine to the updated value (E7DF) and will report back later on today...

I have noticed that usually different ROM IDs carry different values for things such as 2 byte load, 2 byte RPM, etc....should I be worried that this code above was for ROM ID 88590015 or are the Periphery codes universal for the USDM Evos?

BTW...I am also using the Rear o2 sim patch for my ROM ID found in this link... https://www.evolutionm.net/forums/sh...d.php?t=333820