Looking for a fule pump on my 2004 audi a4 avant 1.8t

You can raise the brightness with the dash light dimmer control have you tired that?

Check bulbs and fuse. If they are fine then check the switah. If OK it is wiring.

could be sender or pump. do not run the engine until you're sure you have a good pump. Does it blink on and off--coming on mainly at idle? This would be normal for an old engine. If it stays on and the pump is bad, you will ruin your engine. You can try replacing the sending uniot, as that is cheap compared to the pump, but don't run it long to check new sender. If new sender stays red, shut down and replace pump.

change thermost and/or water pump

Not necessary to replace any components, but the engine Exhaust Gas Recirculation (EGR) system needs to be cleaned inside together with the intake manifold, (both EGR throttled valve and intake manifold).

loss of power sure car is breaking !!! some of the abs sensor broken or dirty

try changing the coolant sensor then all should be fine

That's the motor-management warning light. Meaning: serious errors are being detected by the motor-management computer (= ECU). You should have a dealer readout those ECU faultcodes using VAGCOM to determine the cause a.s.a.p, before (more) harm is done to the engine.

Please be aware that your motor could also switch to "failsafe" mode when too many severe errors are detected, meaning it's terribly slow to drive and turbo-pressure is nearly non-existing.

leave it to a specialest or maindealer