dead speedo/tach?? where to start

[portlandareae28]

my buddies m535's speedo and tach went dead on him, he doesn't have a computer yet, so I will be the Liason as I will be helping him with it anyway.. We are both fairly new to E28's bmw owners for awhile but not E28. Would this be a battery problem that I have read so much about?? Thanks

Brian

[Dave_in_VA]

Yep it sounds like the SI batteries have died.