HELP Code 34 (Auxiliary fan relay faulty)

I own a 1994 E320

Each time i diagnose my car, it gives me a code 34 (Auxiliary fan relay faulty) on pin 7, but the auxilary fan works just fine when the engine temp exceeds the preset value (about 80 Celcius for my car). So what might be the problem ?

well that's the problem.  The aux. fan isn't supposed to come on until you get to 107'C.  Is it coming on just above 80?