I had a similar problem on my '02 Tacoma - the dash was dark but I also had a left brake light out (tail light part of the bulb was OK). So I replaced the tail/brake light bulb, plus fuse #8 (old one was shorted but I replaced it anyway) and relay E, and both the brake light and dash lights came back on! I'm frankly not sure whether it was relay E or the bulb that I swapped out that did it, but all 3 parts were WAY cheaper than just having having the car diagnosed.
Aug 11, 2016 at 12:16 PM