Narrative:

We were established at our cruise altitude of FL400 for about ten minutes when the first officer noticed his altimeter was jumping up and down two hundred feet. Also; his vertical cue on his flight director was flashing on and off with his airspeed fluctuating plus and minus ten knots. Shortly after; we received a FMC message for right IRS drift. We could not locate it in the ops info section of the QRH. We texted dispatch about the FMC message and they said; 'standby; we will work on it.' we then received an FMC message 'verify pos: IRS IRS.' this message we did find in the ops info section of the QRH. It directed us to the FMC navigation check. We ran this checklist and found that there was no data for the right IRS on position reference. I selected the IRS on the overhead to both on left. This time the autopilot disengaged. It was not indicated in the FMC navigation check that this would take place so I decided to place the IRS switch back to normal. Shortly after the first officer's attitude indicator was in a constant left turn and I had an amber roll annunciated on my pfd (primary flight display). Shortly after; we lost all data on the first officer's pfd. At this time we decided it was best to get the aircraft on the ground. We [advised ATC] and chose ZZZ as our diversion airport. On our way into ZZZ and passing through 15;000 ft. We received an right IRS fault. We were already being vectored onto final and we decided to not perform the right IRS fault checklist and landed in ZZZ without any further issues.

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Original NASA ASRS Text

Title: B737 Captain reported irregular indications on First Officer's flight display resulted in a diversion.

Narrative: We were established at our cruise altitude of FL400 for about ten minutes when the First Officer noticed his altimeter was jumping up and down two hundred feet. Also; his vertical cue on his flight director was flashing on and off with his airspeed fluctuating plus and minus ten knots. Shortly after; we received a FMC message for right IRS drift. We could not locate it in the Ops Info section of the QRH. We texted Dispatch about the FMC message and they said; 'Standby; we will work on it.' We then received an FMC message 'verify pos: IRS IRS.' This message we did find in the Ops Info section of the QRH. It directed us to the FMC Navigation Check. We ran this checklist and found that there was no data for the right IRS on POS REF. I selected the IRS on the overhead to both on left. This time the autopilot disengaged. It was not indicated in the FMC Navigation Check that this would take place so I decided to place the IRS switch back to normal. Shortly after the First Officer's attitude indicator was in a constant left turn and I had an amber roll annunciated on my PFD (Primary Flight Display). Shortly after; we lost all data on the First Officer's PFD. At this time we decided it was best to get the aircraft on the ground. We [advised ATC] and chose ZZZ as our diversion airport. On our way into ZZZ and passing through 15;000 ft. we received an R IRS Fault. We were already being vectored onto final and we decided to not perform the R IRS fault checklist and landed in ZZZ without any further issues.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.