Coolant light randomly stays on

[panason1c]

My 2002 ML 270CDI has just developed a problem.....The coolant light randomly comes on and off during a journey , sometimes it will stay lit for a couple of minutes or sometimes longer or it might not come on at-all for a few days but today it lit up much more frequently and randomly came on and off many times times during a journey, the coolant is up to the full level and the engine runs at normal temp........the strange thing is that whilst the coolant lamp is lit the the radiator fan doesnt operate but also the heated seats will not work, when the switch for the seats is activated the 'on' lights in the switch just flash for a few seconds and then they disable....but when the coolant light goes out the seat heaters will work normally!.
Any ideas?
Thanks in advance.

 

[television]

I have checked all 1657 faults but nothing shown for any of the problems.
It would seem to me to be a wiring ground fault, or poor fuse connection.

Sorry, cant say anymore. Malcolm

 

[panason1c]

Thanks anyway television, i will check all connections, etc.

 

[panason1c]

Sorted (i hope, as the light has stayed off so far!) ........it was the fan control unit!....The new price for the part from MB is £500+ !!...... but i found a used one for £50 (-:

My 2002 ML 270CDI has just developed a problem.....The coolant light randomly comes on and off during a journey , sometimes it will stay lit for a couple of minutes or sometimes longer or it might not come on at-all for a few days but today it lit up much more frequently and randomly came on and off many times times during a journey, the coolant is up to the full level and the engine runs at normal temp........the strange thing is that whilst the coolant lamp is lit the the radiator fan doesnt operate but also the heated seats will not work, when the switch for the seats is activated the 'on' lights in the switch just flash for a few seconds and then they disable....but when the coolant light goes out the seat heaters will work normally!.
Any ideas?
Thanks in advance.