The PinScore PJ-7999-HV pinball power supply replaces broken, failing, or missing power supplies in Williams System 3, 4, and 6 pinball machines. The PJ-7999-HV is engineered from the ground up with modern technologies and manufacturing techniques. Built around new switching power supply technology, PinScore power supplies boast nearly twice the efficiency and half the heat output of the original late 1970s and early 1980s-era designs found in the affected pinball machines.

New safety features such as short-circuit and over-temperature protection increase reliability and protect your game from other faults. Extra power output enables your machine to effortlessly run game upgrades such as LED displays.  As a drop-in replacement, the PJ-7999-HV includes everything you need to replace your game's power supply - no soldering or engineering experience required!

The PJ-7999-HV is a complete replacement for the original power supply, for powering both the game electronics and high-voltage displays.


  • Plug ‘n Play installation; no soldering required
  • Increased efficiency over original power supplies
  • New switching regulator technology engineered for efficiency and reliability
  • Higher output to effortlessly power game upgrades
  • No-solder drop-in replacement - No soldering or experience required
  • LED status indicators for easy troubleshooting
  • 5-year warranty
  • Made in the USA

5V Switched Regulator Power Supply

The main 5-volt DC linear power supply has been replaced and completely redesigned to the cool, reliable switched-regulator style power supply used in modern computers. Thanks to high efficiency and little waste heat, switched regulators require no large metal heat sinks. This is an eco-friendly, "green" power supply that keeps your backbox internal temperature cooler and lowers your machine's overall power consumption. It is also short-circuit tolerant, so an errant screwdriver or a fault in the 5-volt circuit will not harm the power supply. 


Specification  PJ-7999-HV  Original Power Supply
Voltage Output 5V  5V
Efficiency 93%  48%
Peak Current 8 Amps  4 Amps
Peak Power 40 Watts  20 Watts
Continuous Current 6 Amps  3 Amps
Continuous Power 30 Watt  15 Watts
Short Circuit Protection Yes  No
Over-Temperature Protection Yes  No
ESD Protection Yes  No
LED Status Indicators Yes  No 

Kit Contents

Qty Part # Description
1 PJ-7999-HV PinScore PJ-7999-HV Pinball Power Supply
4 4006-01003-05 6-32 x 5/16” Machine Screw 

Supported Games

The PJ-7999-HV is a drop-in replacement for Williams System 3, 4, and 6 games and shuffle alleys.

Blackout Laser Ball Time Warp
Contact Lucky 7 Tri-Zone
Disco Fever Phoenix Aristocrat Shuffle
Firepower Pokerino King Tut Shuffle
Flash Scorpion Omni Shuffle
Gorgar Stellar Wars

Taurus Shuffle

Hot Tip World Cup

Topaz Shuffle


  • Installation time: about 10 minutes.
  • Tools required: ¼” nutdriver and/or Phillips screwdriver (varies by game).
  1. Open your game.
    1. Unplug the main power from your pinball machine.
    2. Carefully remove the game backglass (Check owner’s manual for specific instructions) and open the backbox door to reveal the game’s electronics.
  2. Locate and remove the old power supply.
    1. The power supply is typically located on the right side of most Williams pinball machines.  The board will have a large heat sink on it.
    2. With the main power disconnected, unplug all connections from the power supply board.  The plugs are uniquely keyed with special blocked pins to ensure you replace them in the correct locations.
    3. Unscrew the mounting screws on the old board and remove the board from the backbox.  Save the screws for the new board.
  3. Install the PJ-7999-HV board.
    1. With the existing screws, mount the new PJ-7999-HV board into the existing holes.
    2. Reconnect all the plugs
    3. Verify Installation.
  4. (Optional) Remove the High Voltage fuse if using PinScore LED Displays
    1. PinScore LED displays do not use the high-voltage secton provided by the PJ-7999-HV.
    2. If your game uses PinScore LED Displays, you may remove the fuse labeled F1 to disable the high voltage power supply and reduce the risk of shock from the displays. Save this fuse with the game in case you decide to re-install the original plasma-style displays.
  5. Double-check all connections, plug in the machine, and turn the game on.
    1. The PJ-7999-HV LED voltage indications will illuminate to show proper operation of the input and output voltages from the board.
  6. Play Pinball!

PinScore LED Displays

If your machine is using PinScore LED displays, you may choose to disable the high voltage section of the PinScore power supply. This will reduce the risk of electric shock.  To disable the high voltage section, remove fuse F1 from the power supply board.



The LEDs in the PJ-7999-HV indicate the presence of voltage and are a useful tool for troubleshooting a non-functional machine.  If the LED is not lit, it can indicate a problem either with the PJ-7999-HV or the voltages supplying it.  When the PJ-7999-HV is functioning correctly, all LEDs should be ON.

The +5V and +/- 91V circuits can shut down because of shorts.  If the LEDs are on while other boards such as the MPU are disconnected but turns off when they are connected, there is a short present on that board.

PJ-7999-HV LED Chart

LED Purpose
D1 +91V Plasma Display
D2 -91V Plasma Display
D4 +18V Feature Lamps
D5 -12V Logic Supply
D9 Flipper B+
D10 +5V Logic Supply
D13 +12V Logic Supply
D14 Solenoid B+

Test Points

The test points on the PJ-7999-HV provide another tool for troubleshooting and verifying correct voltages in the machine.  The following table indicates acceptable voltages to be measured at the various test points located on the board.  To use the test point, use a digital multimeter (DMM), with the black/ground lead connected firmly to a ground point such as mounting screw, and use the red/positive lead to check the test points.  Make sure to set the multimeter to the correct range and voltage type (AC/DC) for a proper measurement.

Measured values should fall within the tolerance range specified in the Test Point chart.  Values outside of these ranges could cause erratic game behavior such as intermittent resets or weak solenoids.

PJ-7999-HV Test Point Chart

Test Point Tolerance Tolerance, V Purpose
+5V +/- 1% 4.95V, 5.05V Logic Supply
+12V +/- 3% 11.64V, 12.36V Audio Supply
-12V +/- 3% -11.64V, -12.36V Audio Supply
+91V +/- 5% 86.45V, 95.55V Plasma Display
-91V +/- 5% -86.45V. -95.55V Plasma Display
+18V +/- 5% 17.1V, 18.9V Feature Lamps
+40V +/- 5% 38V, 42V Flipper Voltage
+40V +/- 5% 38V, 42V Solenoid Voltage


The fuses on the PinScore power supply should not blow under normal operating conditions.  If you find a blown fuse in your PinScore power supply, locate the problem before replacing the fuse.  A blown fuse indicates a short elsewhere in the machine. Refer to the fuse chart to help locate where to search for the short.  All PinScore fuses are rated at 250V.

Never substitute a fuse with a higher current (amperage) rating. This will void your PinScore warranty and create a fire hazard.  If a fuse blows repetitively, it is a problem elsewhere in your game.

PJ-7999-HV Fuse Chart

Fuse Current (A) Voltage Purpose
F1 3/8 A Slow-Blow 250V Plasma Display Source*
F2 10 A Slow-Blow 250V Flipper+ (FLPR+)
F3 2.5 A Slow-Blow 250V Solenoid B+ (SOL_B+)
F4 8 A Slow Blow 250V +18V Feature Lamps
F5 4 A Slow Blow 250V Logic, +/- 12V
F6 Not Used - -

* Removal of F1 is recommended if using PinScore display systems


All PinScore power-supply products are covered by a 5-year, transferrable warranty.  Should your power supply fail, contact your distributor for repair or replacement options. PinScore products will be repaired or replaced at the distributor’s discretion.

PinScore power supplies are a replacement product for aging pinball machines. While PinScore power supplies are carefully engineered to replace as many high-failure parts as possible and retain robustness, there remains a possibility that other parts of your machine may need to be repaired before your game will function correctly.   These parts include but are not limited to your machine’s transformer, wiring, and fuses. The PinScore warranty does not cover damage caused by improper installation, faulty wiring, and incorrect aftermarket repairs.


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