Drawing revision checks, done before the shop builds the new rev.

A customer sends Rev D while Rev C is cut, kitted or already on the board. Somebody has to find out what truly moved, then what it reaches: wire cut to the old length, terminals and connectors on the shelf, finished harnesses in stock, released work orders and blanket POs still open.

In the proof of concept, AI reads copies of old and new drawings you already handled and drafts a change list: each difference and where it sits on both sheets, the open orders and stock it touches according to the exports you send, and the questions for the customer. Your reviewer sets that list beside what your team really found.

The revision block is a summary of the change, not the change. ASME Y14.35, Revision of Engineering Drawings and Associated Documents, covers identifying revision locations, the revision symbol and revision history block entries, and its 2014 edition offers three methods for multi-sheet drawings: drawing level, sheet level, and every sheet at one level. Under the sheet method, sheet 3 can sit at a different letter than sheet 1. Customers following that lettering skip letters such as I, O, Q, S, X and Z, so Rev H to Rev J is the next revision while Rev H to Rev K means one never reached you. Clouds have limits too: Florida DOT's Design Manual tells designers of road plans to cloud only the latest revisions, and a rev two steps ahead of yours shows only the last round. So the draft compares the full content of both files and marks every difference no cloud or block entry mentions.

Harness content lives in tables that don't move together. A drawing commonly carries a wire list, a connector table, a parts list, a block of notes and a dimensioned layout, and a change can land in one without touching the others: two cavities swapped, a wire's color changed and nothing else, a new circuit into a cavity that was plugged, a length edited in the list but not on the layout. The draft matches by connector and cavity rather than row order, because a redraw or a new export can shuffle every line. Customers on automotive-style tool chains may send a structured harness file, KBL under VDA 4964 or VEC under VDA 4968, and that file is read the same way if it is what you received.

A small edit can reach a long way. A heavier gauge can leave a terminal's range. A new housing can mean a new terminal, seal and applicator, and a re-pinned form board and test fixture. SAE J1939-11, revised July 15, 2026, defines a twisted shielded pair at 250 kbit/s for trucks, construction and farm equipment, so moving a data link on or off a shielded pair changes the wire, the termination and the test. A note can change the bar with no wire touched. The drawing's revision and the standard's are separate things, and the publisher of IPC/WHMA-A-620 sells a 795-page redline of Revision F against Revision E beside the 326-page standard itself. A new callout for a class, a label, a test or IPC-D-620A, the design companion dated December 2021, is listed the same way as a moved wire, for your engineer to rule on.

Open work and stock decide what the change costs. From the exports you send, the draft names each released work order, blanket release, cut wire kit, finished harness and connector or terminal lot that sits at the old rev, with quantity and status as of the day the new drawing arrived. It proposes no disposition and picks no cut-in date. For the customer it writes the plain list: which rev the open PO now means, when the change starts, what happens to harnesses already built, and where the new drawing contradicts itself.

Your reviewer. Whoever knows your change handling best gets the job, and the owner makes that choice, often a manufacturing engineer or the document control lead. They mark each list against what happened: differences found and missed, orders and stock reached, questions sent. Include a rev the customer marked poorly, a full redraw and one that arrived mid-build.

After a yes, each new rev gets a draft change list for about 30 days, and a person approves every item before it posts anywhere.

Your engineer rules on each difference and decides what goes back to the customer. Your people still release drawings and change work orders in your own systems, and the same scoring carries through the month.