Hey All!

So my brake lights dont work, my shift is locked and my ABS is wonky. They all share a common fuse and its number 7. My battery is holding at 13.3 volts, the pcb on the brake lights holds at .6 volts. New fuse. Not sure where to go from here other than pulling the harness out and looking along it for corrosion. I know how to solder and deal with electrical components daily so if there is a hard wiring option, let me know. Any advice would be greatly appreciated as this is my first time troubleshooting electrical in my Volvo!

Thanks in advance.

Kyle

Kyle,

The way to find the trouble is this: Use the circuit diagram to locate the physical places you can measure voltage (or probe with a test light). Trace the voltage only while under load. Use a stick, like a snow brush (if you're in a high enough latitude) to hold the pedal in, providing the load. Start at the load side of fuse 7, probing carefully the fuse holder contact, and work your way toward the load itself at the brake lamps.

Your symptoms really do point to the fuse, given the observation your shift lock troubles coincided with the brake light trouble, so go back over this carefully. It is good that you replaced the fuse, because this particular one, for the brake lamps, gets work hardened by the intermittent duty, eventually cracking in the middle of the element.







If you suspect the brake light switch, read this first: http://cleanflametrap.com/brakelights.htm

And here are links to the wiring diagrams from the factory manuals:

http://cleanflametrap.com/91wdm40.jpg
http://cleanflametrap.com/91wdm41.jpg
--
Art Benstein near Baltimore

What engineers say and what they mean by it:
Engineering says: "Test results were extremely gratifying"
Engineers meant: It works, and are we surprised!