Reading a VDA 4987 Despatch Advice Step by Step
You do not need to be an EDI specialist to sanity-check a despatch advice. Here is a practical reading order that works for any VDA 4987 file.
Step 1 - The envelope (UNB / UNZ)
The first line identifies sender and receiver by their EDI codes, plus the interchange control reference. Check: are you the sender? Is the receiver the right plant? The last line (UNZ) repeats the reference and declares how many messages are inside - in VDA practice, one.
Step 2 - Message header (UNH)
Confirms the message type is DESADV and shows the version directory (commonly D:20B). If this says INVOIC, someone sent you the wrong file.
Step 3 - Document identity (BGM + DTM + RFF)
BGM+351 plus the despatch note number - the number your customer's goods receipt will look for. Then the three dates: created (137), shipped (11), arriving (132). References (RFF) link the shipment to the delivery note (CRN) or order number it belongs to.
Step 4 - The parties (NAD)
Buyer (BY), seller (SE) and ship-to (ST), each with a plant or DUNS-style code. A wrong ship-to code sends your truck to the wrong gate - worth a second look every time.
Step 5 - Totals (MEA)
Header-level gross (AAD) and net (AAL) weight. If these are missing, many plants cannot complete the booking.
Step 6 - The packaging tree (CPS / PAC / PCI / GIN)
This is the part that scares people, but the logic is simple: each CPS opens a level of the packing tree, PAC describes the packages at that level (how many, of what type), and PCI/GIN attach the label numbers printed on your VDA goods tags. The receiving plant scans exactly those label numbers.
Step 7 - The items (LIN / QTY)
Each LIN carries the customer's part number; QTY says how much is in this shipment. Cross-check against your delivery note - a transposed digit here is the most expensive typo in EDI.
Step 8 - Trailers (UNT / UNZ)
Segment count and control references. If you edited the file by hand, these are now wrong - recompute or let a validator tell you.
The 30-second version
Envelope right? DESADV not INVOIC? Despatch note number present? Three dates there? Ship-to correct? Weights present? Labels match the goods tags? Part numbers and quantities match the delivery note? If all yes - send it.