Problem

Static garbage on screen.

Purchased a Sprint 2 in non-working condition  Saw a picture of it, monitor worked - it showing what appeared to be static garbage on it.  Got it home and confirmed that yes, it is showing static garbage (first image below).  Turning it off for a couple of seconds and then back on again keeps pretty much the same garbage display, but sometimes gets some sounds out of it (engine and/or screeching sounds).  Moving the self-test switch does nothing  First suspect that CPU is not running, because the screen is static (i.e. not changing while the game is on).

After checking the usual suspects (voltages, loose wires, harness/wire burns because this is an older Atari game…), I yank the CPU to see if I get the same results (to narrow it down to the CPU).  This causes a different effect, a screen filled with a single character and I get sound, so I presume for now that the CPU is working and the problem lies elsewhere.

Doing some research, I find that the game will not come out of reset if any of the coin switches are stuck  Opening the coin door, I see that one of the switches is disconnected completely (broken QD connectors).  It has connectors for all three switch connectors (Common, NO, and NC), so I put new QD connectors on them and reconnect but this does not change anything.

Sticking with the coin switch issue, I try tripping each switch manually and discover that one of the coin switches’ arm wire is bent such that it never springs back high enough to open the switch  Pushing the wire up by hand I hear the click of the switch and she came right up! 

All controls work and all expected images & sounds are there.  The steering is a bit stiff of both sides - if you spin the wheels (hard) they come to a stop pretty quickly, within 2 full revolutions.  I guess I might have to crack open up one of the steering modules to see what’s what.

Solution

Stuck coin switch was causing the game to stay stuck in reset.

Updates

After some additional work on the cabinet, I reattached the filter board and started to see some strange effects.  Cars would get horizontal streaks on them which other cars could crash into like obstacles.  I thought I had messed up the cabinet wiring (ground issue).  Took a few days to realize that the EMI filter board was the culprit.  It is not attached right now - maybe I will fix it later.