Hedgehog......Have you driven it and the lights stay on or did they come on immediately after lubing and before driving. If you haven't driven it, I would drive it first before I tried to clean or repair anything. It's not uncommon for them to come on occasionally. They should go off after a few miles.
As Bob said, the brake fittings only get a few shots. The first time I lubed mine, I greased the heck out of them and couldn't get the coach brakes to release afterwards without rocking the coach back and forth.
Don & Mary
2019 Newmar Dutch Star 4018
2016 GMC Canyon 4WD Crew Cab