Hope someone has some knowledge on this happening. I recently disconnected my battery to remove a permanent battery charger setup I had installed and put back everything as it was. When I started the car up again the park brake light ( park brake is off ) is on as well as the abs light and the yellow exclamation light. They stay on and won’t go out. The car runs fine as before except for these new lights on the dash that won’t go out. Any ideas ? 

Took car into Glenn’s shops so he could pop off the front grill.  Needed to remove to have access to A/C. Taking car into a shop for a system recharge.  It was ‘topped up’ in 2018, but weakened last year to nothing now. i hope it just needs charging.  I’ll keep y’all posted. I tried for a hour+ sitting in a chair in my garage to remove grill.  I have limited abilities due to broken hip. My efforts brought me as close to crying as when I was passing kidney stones years ago. 🥵

“We have an obligation to fight for the world as it should be.” Michelle Obama  

These are the best smarts in Canada, so buy this one.

No. Not necessary to tune.   With the block off plate, no gas will reach the EGR valve. The valve may still open/close - will not do any harm. Our CDIs do not have a NOx or O2 to verify the operation of the EGR.