BMW E39 Webasto fault codes: reading and resetting
E39 how are the Webasto fault codes read?
The factory-fitted Webasto has no separate diagnostic socket, so the codes are read through the car's OBD connector with BMW's own diagnostic tool. Before troubleshooting, make sure a connection to the unit can be made at all.
The Webasto no longer starts - how do I reset it?
The Webasto locks into a fault state after three failed start attempts. Reset: 1. Switch the heater off with the switch or timer and switch it on again. 2. Take fuse F1 (15 A) out and put it back after 5 seconds. 3. Repeat once. The heater tries to start about 10 seconds after the fuse is fitted, and the coolant must be below 60 °C.
What does the Webasto fault code 'circulation pump, open circuit' mean?
The code usually points to the heater's circulation pump, but the fault can also be in the control unit. Check the pump's wiring and connector and the pump itself before replacing an expensive part.