So I swapped out the alternator and now the cluster isn't coming on my GS400. It had done this before but for the life of me I can't get it to come back on. I checked all the fuses people suggested in other threads. I've pulled the battery off multiple times. I charged the battery. Still the cluster won't come on.

The car starts. The Navi/radio don't come on but I can see the screen flash on for a second.

I just don't can't think of what to do next. My guess is there is just some signal or hand shake problem between the electronics.

 

I went through the fuses again and the 120 amp alternator fuse that is in the fuse box next to the battery was blown. I ordered a new one and we will see if that solves all the problems.

It's just weird that I had the exact same problems before and it came back. I do now wonder if my old alternator is good or bad.

 

Generally that fuse only blows if you short the alternator power wire to ground. Another possibility is the alternator going bad and shorting internally taking out the fuse although I've personally not seen this happen. Hope you got a Denso remanufactured alternator most other brands/remans are junk.

About half the car runs off that fuse so replacing it will very likely solve the dead portions of your car.