We had a lot of rain in the last weeks and the DIFF LOCK + VDC, VDC off, ABS, started to randomly flash as I was driving. It was intermittent. It started very lightly, then more solid, but would stop at some point.
It would sometime do it as soon as I started the car, when the car had been parked outside for the night in cold temperature.
I inspected the rear differential DIFF-LOCK switch and solenoid connectors that sits on top of the rear differential.
The connector assembly / wire harness was detached from its metallic support that sits on top of the differential. I also noticed that the wiring harness/connector was full of road grime and oil from the rust prevention oil treatment. It also looked like the wire harness plastic wire loom protection had been undone/broken and was filling with water and road grime.
I cleaned the wire connector area and actual connector with electrical contact cleaner. I noticed that one of the wire had rubbed/cracked and was exposed.
I temporarily covered it with electrical tape and went out for a 45 min test drive. DIFF LOCK light flickering issue was gone. I recovered the wire loom with electrical tape to try to seal it as much as I could.
Connector #1 (on top) = Amber + Black wires are the Diff Lock Switch wire connector.
Connector #2 (on the right) Blue + Grey are the Diff Lock solenoid wire connector.
I contacted the Nissan dealer but they could not locate/sell a replacement part for this wire harness. I will fix/redo the harness with new wires in the spring.
Edit#1 : As per info provided in this threat (see below) it was recommended to order part 24168-EA800 (called Diff Lock Sub). Somehow the Nissan Dealers cannot find the part when they simply look at their part catalog/plans. If you bring the part# you can replace this wire harness. Its roughly 2ft long contains all connectors (seems like a straight forward replacement, unplug old, plug new in.) I will confirm when I install.
Hope it helps.