The logic board of the iMac (Retina 5K, 27-inch, Late 2015), model A1419, 2015, 27-inch Retina 5K. Known faults are being collected.
No guided tree is live for this board yet. The profile, the viewer and manual entry are there on the free plan, and the first sessions on it build the tree.
Checked on 2026-10-29 against 2 sources: corrected. Info '2017' changed to 'Late 2015' and year 2017 changed to 2015. Beetstech lists PPN 820-00291-A (with 820-00134-A and 820-00292-A) as the Late 2015 Retina 5K iMac17,1 board (MK462LL/A, MK472LL/A, MK482LL/A, BTO 4.0GHz i7); eBay: 'Apple iMac 27" A1419 Late 2015 820-00291-A Core i5-6500 16GB Ram Logic Board' (i5-6500 is Skylake, 2015). The 2017 27-inch iMac (iMac18,3) uses 820-00609-A / 820-01134-A per Beetstech. Revision A is a placeholder until Studio records the real revisions.
Open the board in NextProbe, answer the symptom questions and follow the lit point. The free plan includes three guided sessions a month. Your own boardview and schematic stay on your machine.