You have had your Eberspacher D4 for years now and haven’t had many problems with it until now. Intermittently the heater won’t start. When you turn it on you can hear the click of a relay (if the unit is mounted near enough for you to hear it) but that is it. Does this description sound familiar?

If your error code on the control panel is showing 31 or 33 then it is likely your blower motor is worn out or to be more precise the coals on the electric blower motor are worn out. In another article we list a few other Eberspacher error codes.

When the coals are worn out on a DC motor then in certain rotary positions the motor won’t start. You can test this and turn the fan slightly from the front of the Eberspacher D4 before trying to start it again.

The solution here is to get a new Eberspacher blower motor from a dealer and replace the old one. Eberspacher sell these as modules that include the fan and housing for the motor. Buying an Eberspacher blower motor for an airtronic D4 will set you back almost £300 unfortunately, but at least by doing the job yourself you can cut down somewhat on the cost compared to getting the dealer to do the work for you. And because these units are well engineered and easy to service it’ll only take half-an-hour or so to complete the job.