So I have a 2003 HSE that had SLS from the factory - springs long since installed and the ECM/BCM flashed to eliminate the fault light. I recently had an missing issue and I thought I might have a bad coil driver in the ECM so I swapped in a different ECM/BCM set to troubleshoot. Miss turned out to be a bad plug wire, but when I put the original ECM/BCM pair back in the SLS and hill descent lights are now back on. I plugged in my Delphi DS150 to see if there was any way to turn it off, but it doesn't seem to have any functions for the SLS system, or at least not any where I could turn off the lights.

Hoping someone has some experience with these sorts of issues and can provide some guidance. I am going to be putting the truck for sale and would like to have the lights off so the new owners don't have to worry about it.

Thanks in advance for any advice you might have.

Tim

 

The BCU unit has a 'mind of it's own' unfortunately and if it's been unplugged you may need to 'reflash' it to reset the BCU to not recognise the SLS.

 

That is a bizzare issue. The SLS preference is stored in the SLABS ECU which you didn't touch.

Did you swap the instrument cluster? Could the old one have had the lights disabled?

 

Did not touch the Slabs ECU or Inst cluster - it is bizarre!

 

Looks like you just need to get the preference turned back to coils.