Alrighty you electrical guru's...

I've read John Sargent’s response (see below) about fuse #16 being the weak-link in the electrical system of 700 series Volvos... I’ve had the fuse blow and sure enough the plastic is melted surrounding #16...

Selecting Option #2 below…I pulled the fuse block out and there are two purple wires going into the back of fuse #16…not Black…? Which of the two is the supply? Looking at the fuse block (CEU) as it is installed…is the supply the wire on the right or the wire on the left?

In advance, I appreciate those who are more electrically inclined…!

Frank '88 760 284,000mi

[Response:] It was fuse number 16, right? The fuse and fuse holder are simply overloaded in the basic design. There is too much current draw on the fuse holder. It was fine when new, but too many heating cycles weaken the grip of the fuse holder on the fuse after 15 years. This is a very common problem on 700 series Volvos. Unless your car has over 200,000 miles on it, the only part of the central electrical unit that will be bad is the fuse holder for fuse 16. Nothing lasts forever, but fuse 16 is the weak point. The wiring to the CEU should be fine, although high mileage cars can have troubles at other relay sockets. Don't be afraid to pull the CEU, I've done it lots and haven't disturbed anything else in any of our three 700 series. You have two choices:
1. Replace the fuse block with a new, or good used unit.
2. Buy a new fuse holder and power the AC and heater with it.
If you choose option 2, you must pull the central electrical unit out and turn it over. Splice a fuse holder into the lead supplying power to fuse 16. Splice the load side of the new fuse into the black lead supplying power to the heater and AC unit. You must continue to supply power to fuse 16, as fuses 14 and 15 are fed from the supply side of fuse 16. It is possible to intercept those black wires elsewhere, but it is easiest for me at the CEU. If you can get enough slack in the black wire which supplies fuse 16, a red wire nut works great for spicing the new fuse holder in and keeping fuse 16 supplied with power. The fix will be less than $5 US. That is the repair I made to my wife's 86 745T