R350 starter won't turn engine
Current DTC 903C "Component F58kH (Circuit 15 relay) is defective or missing, or the feed line has open circuit"
Any Help is appreciated.
Good luck fellow MB'er
Dan
https://mbworld.org/forums/gl-class-...-resolved.html
After spending several hours with a Mercedes mechanic on Just Answer the problem is resolved.
Turns out that the "circuit 15" relay had no ground due to a faulty fuse box. This is the relay right next to the starter relay. I simply bent the ground lead of the relay up towards the case and clipped a lead to the lug and to a ground point on the body. Car starts and runs fine now. Not pretty but functional.
Guess I need to replace or repair the ground path in the fuse box
Anyone have experience on sourcing a new fuse box and/or How To on doing this?


