Gas/Temp Tauge, Tach, and HVAC Controls

[Mpoweroo1]

Yesterday, as I was driving, Gas/Temp Tauge, Tach, and HVAC Controls just went dead. I was using the A/C and it just stopped as if a fuse blew. Well upon revision, I can't seem to find a blown fuse! The lights for the A/C wont even turn on.

Any help would be greatly appreciated. TIA

[Goya20]

i had the same problem check fuse number 10 in the fuse box. What year is the bmw

[Mpoweroo1]

Sorry, it is a 91 318i.

I checked the fuses and they all looked good. You think I should replace it anyways?

[Jean]

Test the fuse, not just inspect it visually.

[Mpoweroo1]

Test the fuse, not just inspect it visually.

Thanks, I am a little confused as to why the guages went out and the A/C controls too? Are the paired to a similar ground?

[romeomike]

Thanks, I am a little confused as to why the guages went out and the A/C controls too? Are the paired to a similar ground?

Can't answer the why question, but the cluster and AC controls both use ground point G200.

Search for e30_91_modified_090512.pdf as it is the most complete electrical troubleshooting manual (ETM) for the 91 model year. The ETM is very helpful with schematics and a series of tests for troubleshooting the AC system.

[Mpoweroo1]

Thanks for all the help guys!

I replaced fuse 10 and 20 and took out all the relays, cleaned them up and made sure they were seated. Everything is working like a charm!:D

[Goya20]

np

[kwblah]

I have this same problem... already changed fuse 10, 20, and 21. Fuel/Tach gauges and all hvac functions still not working.. what else could it be?

[E30_fiend]

^^^^^^
Si board batteries

[kwblah]

^^^^^^
Si board batteries

So i get that this would affect the gauges in the cluster, but why would it affect the hvac functions?