If yours is a Fendt 312 Vario Typ 339, more than 450 parts are listed here, among them lighting, electrics, and steering and front axle parts.
This page belongs to one version of the 312 Vario: the tractor with Typ 339 on its identification plate. It brings together more than 450 parts matched to that version, so there is no need to sort through parts meant for a different 312 Vario.
A charge warning light that stays on, or work lights that dim at idle, usually point to the charging circuit. For the Typ 339 there are alternators and starter motors, together with push button switches for the dash, such as the red hazard light switch with a lock. There are potentiometers too, including the one that reports the position of the rear linkage. Once that sensor starts to wear, the hitch tends to hunt up and down instead of holding its height.
Workshop tip: before fitting a new alternator, measure the charging voltage across the battery terminals with the engine running, then check the earth strap and the connections at the back of the alternator. A loose or corroded lead gives exactly the same symptoms as a failed regulator and takes minutes to put right. If the alternator really has gone, check the belt tension when you fit the new one. A starter that only clicks often has worn brushes or a sticking solenoid, and there too the cables deserve a look before anything gets replaced.
On the roof and at the rear there are LED work lights and rear lights, with HELLA among the makers, plus beacons and the holders they sit on. Inside the cab you will find floor mats, grab handles and gas struts, for example the strut that holds the front window frame open. Wabco connector heads cover the air brake line to the trailer, while bushes, seals and O-rings deal with worn pivots and slow leaks. Walterscheid and GRAMMER are two more of the makers you will come across. Work lights earn their keep in autumn and winter, when fieldwork carries on well after dark.
The type plate shows the word Typ followed by three digits. If it has become unreadable, compare the reference number on the old part with the details given for each item. If your plate shows a different number, that version has its own page:
The Fendt 312 Vario page brings every version together. Other tractors in the Fendt 300 have their own overviews as well: Fendt 309 Vario, Fendt 310 Vario, Fendt 311 Vario, Fendt 313 Vario and Fendt 314 Vario. For older models and the rest of the range, head to Fendt parts.