Dixie Narco 501-E v4 - Cannot get passed the HD menu

[GazelleVending]

I just got my first Dr. Pepper machine in today, and I'm having trouble priming it.  I press the blue service button, and "HD" displays on the front, but when I press and hold the 2 buttons, the display just scrolls "3402" and then "4026".  It doesn't matter how long I press and hold the first two buttons, this keeps scrolling.  Hoping somebody can help me figure this out.

[Gizmo Vending]

Make sure that the buttons are making contact with the switch.  Those buttons on the dr. Pepper machines can get gummed up with dirt and grime.   You can check that by pressing a selection button and you will hear the switch click.  If it doesn’t click then you can play with the housing behind the button and get it aligned properly.  Also make sure that buttons 1 & 2 are for their corresponding columns.   

[AZVendor]

The numbers following the HD is the lifetime number of vends on the machine of 34026.  If there was a decimal place then it would be lifetime dollars through the machine.  You need to check your #1 and 2 selections switches as Gizmo says.  If they don't react at the same time you won't get to the next level of programming.

[cvending]

Also check your door switch. 

[GazelleVending]

Thank you all for your help!  Button one is coming out of the housing and needs replaced.  Holding the switch in place is a workaround.