On my 2019 Z1000, the EFI light does a constant blink (no pause, etc) just constant.  I've tried charging the battery, double checking leads, etc. Turning the ignition off then on to reset it - nothing seems to work to clear it.   I took it to my dealer and they have had it for 3 weeks and will be another 1-2 weeks before they can even diagnose it. Good dealer - just swamped....

Anyone have any advice for me?  I'm going nutz not having my machine in the middle of mountain riding season... 
Debating about just picking it back up and trying to fix it myself.

I'm handy - but have ZERO knowledge when it comes to electrical systems in these machines and don't have a code reader to even know what it's doing anyway.

I had the EFI light start coming on randomly one day a few weeks ago while out on a ride, machine worked fine.  It would just randomly start to flash, same as yours no code pattern just constant flashing.  Wife noticed that it seemed to do it when going up hills, so we stopped and checked it over.  Pulled the dipstick and it was low on oil so we headed home to get some.  Once I topped it up the light hasn't come back on since.  I don't even know if that light ever references a low oil situation, or if that was the actual issue, but that's my experience with it.  My oil pressure light never came on at all during this.  I check the oil before every trip now and have some under the hood just in case.

Thanks Red - At this point, I'll let the shop diagnose it and just wait it out...  But that's a good tip, and now that I have the service manual, I'm going to take on all the service myself (at least as much as I can).  Waiting a month before I can even have a tech look at it and plug in a code reader is getting really frustrating...

I'll report back here when I hear what the issue was...

Finally got the diagnosis,  Faulty oxygen sensor between the air box and throttle body.  Still have to order the part.
But I got the machine back at least and it's working fine.

They did confirm it was the faulty sensor and was NOT due to dirt, etc. in the air intake.
I put a snorkel and new filter in the machine the first weekend I had it.

[2015 Z Force 800 53/Trail EPS]

O2 sensors are on the exhaust(s). There is an air temp sensor on the intake track but it's after the TB. Here is the EFI system structure for the 1000s and 950s.
 

Yup. The T-Map sensor. But it's in the t-joint after the throttle body.

The engine worked fine while EFI did blinking?

I'm asking because just today the same thing happened to my Z1000 (2018) but the engine is not working properly (runs irregularly and, eventually, stalls).
I'll check tomorrow the filters (fuel, oil and air) and the oil level but I'm guessing that all are ok (checked them before last ride, two weeks ago) and I have to send the machine to the dealer.

Thanks