Starting issue

[Grublet]

Throughout the winter my 05 E270 CDI won't start if the outside temperature is below 9 degrees . The ignition turns on but there is no glow plug light, the cooling fan switches on and runs flat out, then I get EBS and ESP malfunction warning on the dash. if I heat the ECU with a heat gun the car will start. I've had the ECU examined and reprogrammed but still got the same issue. the summer months are not a problem, the glow plug light comes on with ignition, no cooling fan or EBS, ESP malfunction and the car starts as it should. Any ideas?

 

[saff]

Throughout the winter my 05 E270 CDI won't start if the outside temperature is below 9 degrees . The ignition turns on but there is no glow plug light, the cooling fan switches on and runs flat out, then I get EBS and ESP malfunction warning on the dash. if I heat the ECU with a heat gun the car will start. I've had the ECU examined and reprogrammed but still got the same issue. the summer months are not a problem, the glow plug light comes on with ignition, no cooling fan or EBS, ESP malfunction and the car starts as it should. Any ideas?

I had the exact same problem with my 06 E220 CDI. Above 10 deg all would be fine but anything lower would give the same symptoms and directly heating the ecu with a hair dryer would allow the car to start and behave normally. It was indeed a faulty ecu and a local auto diagnostics changed it for a reconditioned unit from Bosch. This was over 5 years ago and the cost then was around £650.
Good luck!