fuel gauge malfunction

[canada5]

The fuel gauge showed that I had no fuel but I knew there was about a quarter tank.
After filling with about $20 the gauge still showed empty. Then I noticed that the engine temperature wasn't registering either. All the fuses seem OK with a visual check. The fuse guide on the box doesn't show a specific fuse to check. The car is an 89 535.
Any information would be much appreciated. Thanks in advance.

 

[onnyap]

There is nothing wrong with your gauge. The problem lies with the circuit board inside the instrument cluster unit Most of the time the culprits are the capacitors and diodes. Also watch-out for the rechargeable 'AA batteries' for leakages. My conclusion is to replace the board with a new one and NOT a used part.