Need help

[HogsFan]

I've got an 07 Yukon xl my abs and stabilitrack service lights come on at same time. I have also started noticing that sometimes when parked press brake to put into rev the shifter won't pull down have to press brake several times then finally lights come on and then shiftes into rev!!!! The dealer said the brake pressure modular had to be replaced $1200 can't guarantee it will fix problem, any help out there...