Hey all

Looking to get some information and hopefully a route to the conclusion.

Short story (seat Ibiza 1.2tsi cbzb) cars over heating and coolant begins to bubble.

This all started after a failed/leaky waterpump replacement and new v belt.

At first the top rad hose wasent getting warm and cabin heaters only blowing cold so I replaced thermostat and now top hose gets warm then hot and after a while bottom hose gets warm but not hot.

At this point I noticed the radiator fans were not coming on and coolant temperature was rising very high.

I removed radiator fan switch connector bridged between the 3 pins and high and low fans begin to work.

Vcds says the radiator outlet temperature is -47c

So I order a new fan switch and get that fitted only to find vcds still reads -47c and the fans still do not come on?

I’m now thinking the radiator is blocked and maybe hot coolant isn’t getting to the fan switch location? Would this be possible?

All fuses on fuse box are ok as are engine fuses.

Any other advise welcome

  • Grand_Possibility_69@alien.topBEnglish
    1·
    1 year ago

    So I order a new fan switch and get that fitted only to find vcds still reads -47c and the fans still do not come on?

    Are you sure you replaced the correct sensor? I’ve seen this multiple times. People have just replaced the wrong sensor. Sometimes also causing problems by installing the wrong sensors as some VAG sensors can fit in place of each other but are electrically different.

    You calling a sensor switch points to some confusion here. A switch would just turn a fan on or off. Only a sensor would show temperature.

    If you’re sure you’re replacing the correct sensor new one is bad or you have wiring problem.

    I’m now thinking the radiator is blocked and maybe hot coolant isn’t getting to the fan switch location? Would this be possible?

    This would not cause the problem you have. Sensor would read somewhere between outside air temperature and coolant temperature if that’s what happens.