I tried to tape them - but they are thick wires - won’t hold.
I may have to buy a soldier - any other accessories to connect them?
Brake light & rear wiper doesn’t work.
Any other tips?
If the splice is at a stress point you may have to insert a little extra wire and use some crimpable butt splices to make the repair.
You can go to most any hardware or auto parts store & find a little kit that will contain most everything you need - the butt splices, a crimper, wire stripper, and maybe even instructions. As Cougar said, though, if it is at a stress point, snip a small piece to take with you and pick up some spare wire to use as extra wire.
Of course, the best way to connect is with solder - so if you’re feeling more ambitious then by all means go out and get an iron and solder. But practice on some old similar wire before you actually try the repair.
There’s no reason to shy away from buying a soldering kit. It’s inexpensive and you will soon find many additional uses for it – in the home as well as your car. That will be the best way to handle most electrical repairs.
My wife’s brother managed to cut the wires in his hatchback attempting to replace the struts. I soldered in a section on each wire and covered the splices with heat-shrinking tape. It took about 15 minutes to make the repair and his wipers and brake light were again operational. The repair held for the five or six years after that that he kept the vehicle.