HP Tuners Section F Disable the Catalyst System Codes
In this article we disable what we hope will be the last of the codes. It is common for LS Swappers to run exhaust systems less the catalytic converter so it makes sense to suppress any diagnostic codes which may surface do to it's absence. There will be an accompanying write up on how to actually turn off the catalyst PCM controls but for now we focus on just the codes.
On my 2001 Siera donor PCM there were two Catalyst System codes, your PCM may be a little bit different:
P0420 Catalyst System Efficiency Below Threshold (Bank 1)
P0430 Catalyst System Efficiency Below Threshold (Bank 2)
[Just Sayin'] There has never been a more suitable code than a 420 for dealing with lighting up and smoking something, and they say GM egineers have no sense of humor [/Just Sayin']
Now let's look at the Black Magic that it takes to disable these codes, we have two controls:
If it was up to me I would break it up into a third control so it would look more like this:
- SES (Enable / Disable)
- MIL (MIL On First Error, MIL on Second Error, No MIL Light)
- Report Code (On / Off)
1. We fire up our laptop and launch the Editor. Open the file we saved in Section F. (Our last saved file is always our starting point).
2. Make changes in the Editor, this time we will make changes only to the Catalyst System codes under Engine Diag \ DTCs. Refer to the cheat sheet below and Disable the SES on these and set the MIL to No Error Reported, some may be disabled already by default:
P0420
P0430
3. Save the changes you made to a new file and call it something like "11 - Disabled Catalyst System Codes"
4. In your vehicle hook up your HP Tuner to the OBDII port and then your USB cable to your laptop, turn the key to the ON position, launch the Editor program, and simply write the new changes to the PCM.
Note: sometimes you have to write the entire tune file to the PCM, sometimes it is perfectly happy with only writing what's changed, more on this later.
More words with each pic: