Help! My Rock-Ola 476 is Mechanical Dead

Hi all,

I’m working on a Rock-Ola 476 jukebox and ran into a problem that I can’t seem to resolve.

Here’s what happened:

* The machine was playing normally
* A record got stuck during transfer (gripper arm jam)
* The mechanism stopped completely

What I’ve done so far:

* Manually freed the gripper arm using the manual rotation control on the gripper motor
* Returned the mechanism to what appears to be the correct “home/park” position
* Verified that:

* the turntable spins freely
* the magazine can be rotated manually (no hard mechanical blockage anymore)
* Checked all fuses (all OK)
* Reset the circuit breakers on the power supply

Current symptoms:

* The mechanism does not move at all
* The magazine does not rotate when powered
* On the power supply board:

* LED #2 and #3 are ON
* LED #1 is OFF (indicating one supply rail missing?)

Questions:

1. Which voltage rail does LED #1 correspond to on the 476 PSU?
2. Could a jam have taken down one rail without blowing the visible fuses?
3. Is there a known failure point on the regulator board or a relay that would prevent the mechanism from powering up?
4. Are there any specific microswitches or “home” switches that would inhibit the mechanism entirely if not correctly engaged?
5. Is there any additional reset procedure besides breakers + power cycle?

Any pointers on where to probe next (PSU, relays, mechanism power board, switches) would be hugely appreciated.

Thanks in advance!

Hello Tapion,
Led#1 is the +32V mech. supply. It has an electronic overload protection (active when overload lamp is on), the circuit breaker and another 2A slowblow fuse inside the PSU. Circuit breakers can be faulty, they may not snap in correctly and remain open when pushed. The mechanism should be completely serviced before you turn on again.
Regards Jürgen