More info would help here, what year passat? What engine? Generally I recommend that flushing the cooling system with OHC belt replacement. If the water pump is driven by the toothed cam belt replace the unit while you're there. This will necessitate coolant replacement. Suggest that replacement of the thermostat be also done at this time.
A leak in a coolant system can usually be fixed by replacing a hose. If the leak is at the end of the hose, a new clamp might be necessary. If the radiator is leaking, the radiator might need to be replaced.
I belive it might
If an engine light is still on after replacing a fan's radiator sensor in a RFW engine the coolant sensor should also be checked. If the coolant sensor is bad it will send an error code to the car's computer.
I'm not a mechanic but, I had to replace my radiator to fix the overheating problem on my 1994. That was the last thing I replaced after replacing the water pump, thermostat, and replaced my fan with a clutch fan. have not had anymore problems with it overheating once the radiator was replaced. Flush the coolant first then replace the radiator. Hope this helps.
You need to check coolant temperature sensor and the water pump.
your radiator needs to be replaced
With the engine cold, put it in the radiator just to be sure there is no air gap. Run it for a short time until it gets warm and coolant begins to circulate. Then install the radiator cap and put coolant in the overflow to the coolant level line.
You are screwed! Get that radiator flushed by a profesional ASAP! ANOTHER SUGGESTION DO NOT RUN THE MOTOR HAVE IT TOWED TO A PROFESSIONAL. IF YOU DID RUN THE ENGINE GOODLUCK BUDDY HOPEFULLY IT DIDN'T AFFECT THE ENGINE IF SO YOUR GONNA HAVE A HELL OF A TIME REPLACING ALL THOSE HOSES AND YOUR RADIATOR AND HAVING YOUR COOLANT LINE REPLACED.
i would have replaced water pump long before replacing radiator. also check engine oil to see if it has engine coolant mixed in.if it has then the problem is more likely to be a bad head gasket
Because the motor is running to hot try flushing your radiator and putting new coolant in.
The radiator cap might need replacing.
Check the radiator hoses. The coolant is either leaking out of the new radiator, or it is coming from a radiator hose. The water pump may be leaking. Hose clamps may be loose.