
The headline coordinates take you to a defibrillator.
Find the four digits on it.
ABCD CHECKSUM OF ABCD = 10
Please note I strongly advise you to work out all multis in area first so that you won't need to retrace your steps
The cache can be found at: N 50° 46. (A+6) (C+3) (B+2) W 4° 14. A C (D+1)