Hello everyone,

I have a GM Vectra B from 1999, produced in Brazil for LATAM market, it uses C22NE 2.2l 4cil petrol engine with Bosch Motronic M 1.5.4 OBDII? ISO9141

I am trying to figure out at what coolant temperature does the ECU activates the radiator fans 2nd-speed. There`s a bunch of misconception here as some mechanics say its 203F (95C) others 208F (98C) --dash reading.

It happened sometimes were temperature got higher before it activates.. Normally it doesn’t go over 198F (92C) but in some instances went to 208F (98C)… I am not sure if this is a normal behavior or something wrong in the cooling system or gauge reading.

I even bought an infrared thermometer trying to figure out if it was indeed “overheating” but couldn’t reach to any conclusion, since it variates slightly every time I measured it.

Btw everything is new (radiator, water pump, thermostat, cooling hoses, sensors) engine was rebuild 3 years ago with OE cyl head gasket, bolts etc and drove 25k+ miles since then. Besides these temperature raises, never had a single issue.

Would be cool if someone could see the stock ECU file for this application and find out… this has been bothering me for quite a while…

Thanks!