I am sorry, but he wouldn't have to ask for help, if he knew exactly what the problem is.

I admit, I didn't read all replies, so someone might have already sugested this one.
Does your vehicle have a third brake light?
It probably does, check all the light bulbs for correct wattage.
Sylvania bulbs have partnumbers or model numbers on it, but no wattage, I believe.
All stop lights are 21W light bulbs. If one of them is less than 21 watt, you may get intermittend "Check Light" dashboard triggers.
It could also be, simply a bad connection, sometimes wire crimps look good but are broken inside the wire insulation. Way to find out, just pull on it, if it stretches, the wire is broken inside.

__________________
Mostly, I don't know notin, I just know where to look.
I am looking back, to over 30 years in Electronics Design.
Electrons don't care if they move in a car, computer or relay!

95 W124 E320 M104.992 - Because, I love to repair, naaaah!
Over 221,000 Miles
Cheers,
Norbert