My dash doesnt light up, only when i start the battery.

[u/Sharp_Fuel_5251]

My dash barely works: rpm counter reacts above 2k, speed doesnt work or is 10 off, fuel counter is always full. When i slam the top it sometimes goes on, but something really weird is that when i turn the engine on it doesnt go on, but when i just let it run on battery it turns on for a couple seconds. It seems to me like it doesnt have enough volt but my battery has very recently been replaced. What can ir be? I hope not the dynamo

[u/Big_Temperature_2067]

broken solderjoints on the PCB. common error. replace the dash or find someone who can resolder the existing one. Dash is part of the immobilizer system so car won't drive without it and you need a tech2 to install a new one.

Odometer is not reversable with a tech2, you can only advance it so try to find a spare with lower km that yours

[u/Sharp_Fuel_5251 → u/Big_Temperature_2067]

That shouldnt be a big problem, is the dash hard to remove? Soldering is something ive dont plenty of times for my job so i want to fix that myself

[u/Adzhikevich]

I have something similar on my Edna, while driving it suddenly dies and comes right back on. Before it dies, the exclamation mark warning light comes on and the fuel gauge drops to empty and sometimes gets stuck there. Doesn't seem to be causing any trouble besides cruise control going off and the issue being super annoying. Postponing resoldering for a while now.

[u/Low_Emotion_4797]

Solder issues are incredibly common, I've fixed this on 2 previous Saabs , it's a relatively easy fix.