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FREE SHIPPING on US orders over $75 (oversize excepted) • Quality used E36 & E46 parts • Every part inspected & graded
3 Series Parts

Diode assy

BMW Part Number:12 31 1 727 748
12311727748short number 1727748
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One email the moment one is listed — nothing else.

Fits E36 — 316i, 318i, 318is
Select your vehicle to check fitment

Genuine BMW Part

Photos coming soon — see the BMW diagram below

Diode assy – BMW diagram07 View BMW DiagramSee this part on the official exploded view

This is a genuine BMW diode assy, part number 12 31 1 727 748. The number stamped on the part is 12311727748; BMW's catalog files it under the short number 1727748. You will find it on our Electrical shelf, under Alternator with motor and mounting.

It fits the E36 sedan and coupe (318i, 1992–1999), with the M40 or M42 engines — and the European-market versions.

BMW draws it on 4 diagrams, among them Alternator Parts 65a (12_0484) and Alternator Parts 65a (12_0551). It weighs about 194 g (0.4 lb).

We have not had one on the shelf yet. Request it and we will tell you when one comes off a car.

Details

BMW Part Number12 31 1 727 748
Also written as123117277481727748
QualityGenuine BMW · OEM

Every used part is inspected and graded before listing. Condition grades:

  • Good — minimal wear, fully functional.
  • Fair — normal wear, fully functional.
  • Acceptable — visible wear, still functional.

Returns: 30 days if a part arrives damaged or isn't what the listing described. Full policy.

Shipping: Ships within the US. Orders ship within 1–2 business days; small parcels ship free on orders of $75.00 or more. Oversize items ship at a flat $49.99 each — free shipping does not cover them.