Bad Jumpstart. ECU Fried?

[danielmakana]

Upon returning home from a month long trip I go to drive my e30 only to find that the battery was completely dead. No lights or anything. This has happened before and I used a charger. However it wasn't available at the time so one of my friends offered to jumpstart my car. Initially they connected the cables with reverse polarity. It was only for a short time. Maybe 20 seconds but I think this is when all the damage was done. After fixing the cables the car started fine but I noticed that my tachometer, the fuel economy gauge, the obc, the radio and my interior lights were not working. It is as if they have no power going to them. I drove the car around for about 25 minutes like this to get the battery charged up and the car seemed to drive fine.

If anyone has any suggestions on what I can do to remedie this it would be greatly aprreciated.

[dashboardmonkey]

Check your fuses.

[danielmakana]

I think I did a pretty good job of checking the fuses in the fuse box. Are there any other fuses to check?

[e30this]

You might not see the fuse is bad by looking at them.
I say find the ones in the fuse box that control them specific things and replace them with new ones.

[danielmakana]

e30 this I did what you said and it is still a no go :(

[DerRoteBaron]

8)8)

e30 this I did what you said and it is still a no go :(

I had this problem recently. fuse number twentysomething was blown. it was a 7.5 fuse, double check

[danielmakana]

Thank you everyone so much. After rechecking the fuses I found that I thought that originally thought fuse 20 was fuse 21 because of a small gap in the fuse box which I thought was a slot for a fuse. Everything seems to be working now:)

Thank you R3V

[JuanPabloBongto]

I made the same mistake, and had to replace the alternator and battery. So it sounds like so far you've got away with murder.

Also the ABS relay is probably toast.