Larry,
I loosened the back upper corner of the door panel and with some effort and minimal loss of blood due to scraping my hand I was able to reach into the door cavity and easily push the locking pin up from the back of the door lock. I could see no cause for this failure to happen. Before I put the panel back I tried both the key and plunger several times without incident. For good measure I drove 4 miles to town and back on my bumpy gravel road; everything still works so I put the panel back. Keeping my fingers crossed. I hope this answers your question. 
Dake
’86 Westy
> On Jul 8, 2015, at 1:15 PM, Larry Alofs <lalofs@GMAIL.COM> wrote:
> 
> So, could you describe the exact cause of the problem?
>   Thanks