ventps

hi, my '06 C220 CDI overheating warning indicator came on without any of the normal expected problems. The technician advised the diagnostic indicates that the fan and/or the controller box needs to be replaced. this is a bit of trial and errot though? any better suugestions to possible identification of what should be replaced. the temp goes up to about 82~85 when the alarm comes on.

dj_rzn

It also might be the thermostat.

Glyn M Ruck

87 - 90 deg C is normal operating. Benz thermostats are supposed to fail open but it's worth checking.

The fan & fan controller are one unit.