Troubleshooting Superchips Performance Tuner Not Communicating with GMC Sierra

Updated 09/12/2024 | Published 06/27/2018

Question:

I have a 2004 GMC pickup and when I hook the super chip tuner to it it will read the vehicle information but when I try to tune it to the vehicle will not respond to the tuner what could be the cause of this

asked by: Lee S

Expert Reply:

I have spoken with my contact at Superchips before regarding the exact issue you are having with your Flashpaq F5 Performance Tuner # SU2845 on your 2004 GMC Sierra. He said that this can sometimes happen on trucks that have a remote start or aftermarket stereo installed. If this is the case on your truck, check the wires going back to the OBD-II port to see if there is anything spliced into the purple wire. If there is, go ahead and remove it.

If that doesn't work, also see if it sounds like the door chime is coming from behind the stereo in the dash, instead of the door speakers. If it is, you will want to pull the stereo out and disconnect the chime box - which is just a small speaker. Doing this should allow the tuner to communicate with the truck and you should be good to go.

Just let me know if you the issue still persists and I will be happy to look into this further.

expert reply by: Chris R

Moses A.

9/12/2024

Hello Chris, I was just experiencing the same issue! wouldn't you know there was a wire spliced on the purple of my OBDII. Removed it tuner is now working as it should! Thank you, Moses