pdxgen2

I know the fans come on with the a/c.....

in my old school 1991 VW GTI 8V, which my xB replaced, there was a thermoswitch in the radiator that controlled the fan on/off and fan speed....

I don't see such a thermoswitch in the xBs radiator....

So, what controls when the fans come on without the a/c on?

Are they controlled by the ECU? and if so, can the ECU be reprogrammed by someone with the computer setup to have the fans come on and turn off at the temperature of my choice?

Please don't guess, reply if you know...thanks!

Greg S

iTrader: (1)

The fans come on when the coolant temp sensor reaches either 200 or 205* F. I can't remember which off hand but I've watched mine do it. Pretty sure they are controlled by the ECU, not 100% on it though. If they are you would have to talk to Orange Virus Tuning as they are the only shop to have cracked the coding for the Toyota ECU we use. Honestly it's probably not worth it for the money you would have to spend reprogramming the ECU. What temperature are you waning the fans to come on at? The coolant normally sits at 1868 F when warmed up and the coolant temp sensor is set to keep it pretty close to that.

Just double checked my service manual and yes the fans are controlled by the ECU.

pdxgen2

Thanks Greg...meh, if it is something that can only be done by that place, I'll figure something else out...I guess I am use to my GTI, which you could install a lower temp fan switch to have the fans come on at 185 degrees instead of 195 and a lower temp thermostat as well...there have been a few times this summer where I was sitting in a drive thru and the xB got so hot that even with the temp controls switched on cold (ac not on), there was nothing but hot air coming thru the vents....and yes, Ive checked everything out and everything works as it should coolant system wise except its just too hot under the hood, particularly with the damn catalytic converter in there....I am not impressed with the amount of heat and lack of cooling/ lack of ventilation of the engine bay with this car, so I will make some changes of my own to correct it....

Thanks for your help!!