Power Supply problem with Pinbot..

learpilot2

Member
Joined
Jul 12, 2009
Messages
167
Reaction score
0
Location
HILTON HEAD ISLAND, South Carolina
I have a pinbot that has a low dc voltages on the power supply output pins of jacks 3j6, and 3j5. Any idea what to troubleshoot in the board, or is the problem with the main transformer?

My measured votages off the power supply board are:

J5 connector:

pin3 -99.5vdc good
pin4 +105.4 vdc slightly high (+90 to +105.0)
pin6 +2.74 vdc LOW (+4.9 to +5.2 normal)

J6 Connector:

pin2 -14.2 vdc good
pin6 +14.26 vdc good
pins 7,8,9 +3.03 LOW (normal +4.9vdc to +5.2vdc

Any ideas?

I am told the game will not work with 5v output pins that low.
 
I will assume that you have verified that fuse F5 & F6 are both good.

1. Test BR1 to verify that it is good.
2. Test Q5 and verify that it is not shorted to ground.

Your +5vdc problem is 1 of 3 things.
1. Bad BR1
2. Bad Q5
3. Bad IC1
 
I would see if anything on the power supply board is heating up first. A lot of times a bad component will reveal itself by getting really hot. The first thing I would suspect is the voltage regulator but there's a lot more to the circuit than the conventional bridge, cap, regulator power supply. It's a more complicated +5VDC power supply circuit than older solid state games. That said it still should be fairly straight forward to trouble shoot.

Here's Clay's test procedure from pinrepair.com:

http://www.pinrepair.com/sys11/index1.htm#testran0

Fixing Bad Power Supply Voltages.
Of course check all power supply fuses first using a DMM and removing the fuses from their holder.

If the high voltage (+/- 100 volts) is missing or low or high, the score displays will not work. The HV section of the power supply will need to be rebuilt. The input 90 volts AC (3J1 pin 4 and pin 9 pre-Taxi) comes directly from the transformer, so there should be no issues with that (unless power supply HV fuse(s) are blown).

If the +5 volts is high, suspect a bad 2n6057/2n6059 voltage regulator on the power supply.

If the +5 volts (J6 pin 7,8,9 pre-taxi) is low, check J6 pin 6 (pre-taxi) for +12 to +15 volts DC. If this goes lower than 11 volts, there isn't enough "headroom" for the power supply to make +5 volts, and the game will not boot due to low +5 volts. You can also check the input AC voltage at 3J1 pin 10 and pin 11 (pre-taxi, should be about 12 volts AC). If the input 12 volts DC is low at J6 pin 6 (pre-taxi), put a DMM on low AC volts, and place the test leads on power supply capacitor C10. This should show less than .3 volts AC. If it is greater than this, replace cap C10 (15000 to 18000 mfd 20 volts). If J6 pin 6 (pre-taxi) is still below 12 volts, replace the BR1 bridge rectifier on the power supply. This should fix any low 12 volt DC input problems.

If J6 pin 6 (pre-taxi) is +12 to 15 vdc, this means the BR1 bridge rectifier on the power suppy is good as is cap C10. Next this power goes to IC1 chip (723PC) and Q5 (2n6059/2n6059) to make regulated +5 volts. This should be 4.9 to 5.2 vdc (J6 pins 7,8,9 pre-taxi). If this voltage is low, first replace Q5 (2n6059/2n6059).

Lamp matrix voltage on pre-Taxi power supplies include 3J4 pins 5,6,7,8 (+18 vdc) and 3J4 pins 9,10,11,12 (ground). On Taxi and later power supplies, the lamp matrix power does not go to the power supply board at all (it is wired directly to the CPU board at 1J4 pins 1,2,8,9 and grounded at 1J5 pins 1,2,6,7). If the lamp matrix voltage is missing, the lamp matrix won't work. Power for this is supplied by a bridge rectifier mounted to the metal backpanel of the interior backbox, and the huge blue capacitor and fuse next to it.

On pre-BigGuns sys11 games, the solenoid voltage on the power supply include 3J3 pins 6,7,8,9 (+34 vdc) and 3J4 pins 1,2,3,4 (ground). This is the lower voltage solenoid power. Power for this is supplied by a bridge rectifier mounted to the metal backpanel of the interior backbox. The high voltage (50 to 70 volts DC) solenoid power is supplied by the smaller flipper power board beneath the power supply in the backbox. On sys11b games Big Guns and later, the Auxiliary Power Board has both the 35 and 70 volt solenoid voltages (there is no flipper power board and there is no backbox mounted low-power solenoid bridge rectifier). Also the power supply will *not* have a 3J4 connector for solenoid power.

The Auxiliary power board on sys11b games Big Guns and later handles the solenoid voltages completely: J10 pins 1-4 is solenoid ground, J11 pins 8-10 is +35 volts DC, and J11 pin 2-5 is +70 volts DC. The A/C relay is also mounted on the Auxiliary Power board (formerely mounted under the playfield on earlier games), and turns on and off +35 and +70 volts on the Auxiliary power board at pins J11 1-5 (35 volts) and J12 pins 9-12 (70 volts). This is done in conjunction with the A/C driver transistors which control either a flash lamp or a coil.

Testing the Power Supply.
Another good idea is to test the power supply before powering up the CPU board. This is pretty easy to do. On older power supplies, the two square plugs at the bottom of the power supply is the input power. The two plugs J5 and J6 at the top of the power supply is the output power. To test the power supply, on pre-Taxi games remove the two plugs J5,J6 from the top of the power supply, and turn the game on. On Taxi and later games the J5 connector is renamed J2 is at the bottom left corner. Check these voltages on these plugs with a DMM:

J5 connector (pre-Taxi) - high voltage for score displays:

* 3J5 pin 1 = ground (left most pin)
* 3J5 pin 3 = -90 to -105 vdc
* 3J5 pin 4 = +90 to +105 vdc
* 3J5 pin 6 = +4.9 to +5.2 vdc

J6 connector (pre-Taxi) - logic +5 and 12 volts for CPU board:

* 3J6 pin 2 = -12 to -15 vdc unregulated (left most pin)
* 3J6 pin 6 = +12 to +15 vdc unregulated
* 3J6 pins 7,8,9 = +4.9 to +5.2 vdc
* 3J6 pins 11,12,13 = ground

J2 connector (Taxi and later) - high voltage for score displays:

* 3J2 pin 1 = -90 to -105 vdc (right most pin)
* 3J2 pin 3 = +90 to +105 vdc
* 3J2 pin 5 = ground
* 3J2 pin 6 = +4.9 to +5.2 vdc

J1 connector (Taxi and later) - logic +5 and 12 volts for CPU board:

* 3J1 pins 1,2,3,4,5 = ground (bottom most pins)
* 3J1 pins 6,7,8,9 = +4.9 to +5.2 vdc
* 3J1 pins 11,12,13 = +12 to +15 vdc unregulated
* 3J1 pins 14,15 = -12 to -15 vdc unregulated
 
I will assume that you have verified that fuse F5 & F6 are both good.

1. Test BR1 to verify that it is good.
2. Test Q5 and verify that it is not shorted to ground.

Your +5vdc problem is 1 of 3 things.
1. Bad BR1
2. Bad Q5
3. Bad IC1

Every time I power up, the fuse at F5 blows. It is a 7amp slow blow.

Should that be directing me to a certain componet???

asked, and answered... most likely BR1 is bad
 
BR1 was bad, you were right, now new problem

I replaced BR1, and I got the 5.0 volts out of the power supply.

I sent my pinbot cpu pcb in for repair. Traces repaired, and locked on transisters replaced.

When I fired it up for the first time, everything OK except when you push the credit button to start the game, It will not kick the ball into the plunger area. I hear a constant (chatter) clicking relay under the playfield I think. I reach in to manually kick the ball out, and it plays fine until the ball goes down the drain. The machine does not register that the ball went in the gutter drain between the flippers, and the game keeps playing with no ball. I checked the gutter ball micro-switch, and it works. Also, when the ball lands in the gutter, the ball return solinoid is not kicking the ball into the plunger ball holding area.

I went to the solinoid test menu, and it cycled through all solinoids on the display, however, the test mode activated none of them as it should. I checked for locked on coils with an ohm meter, and found none.

Any ideas??

That ball return function did work prior to the cpu pcb repair, so I am not sure where to look.
 
pinbot 90% alive...

I checked all the edge connectors on the cpu. I then checked all the fuses. I found a 3 amp blown fuse under the playfield (near the back). It was near two small yellow relays. Once I replaced the fuse, pinbot came alive and worked great except for.....

- The 1st LED digit in scoreboard player 1 and scoreboard player 3 is blank.
- When you power up, there is a constant crackling/hissing noises coming from the speakers. Attract mode works fine upon power up.
- After the first game is over, it goes back into attract mode. You start a new game, and it plays OK, however, half the sounds are missing, and all the background music is missing. Everything works, but mostly silient play. This continues indefinitely with future games.
- Sometimes when left alone in attract mode, the machine shuts down, scoreboard blanks, sounds stop, attract mode stops, playfield lights remain steady lit, and a red led labeled "Blanking" on the cpu board extinguishes, while the +5vdc red led and diagnostic red led on the cpu light remain illuminated. It responds to nothing. Pinbot boat anchor.

Turning off the machine, and back on fixes all the above problems until after the first complete game is played. Then same problem. It does not always completely shut down, mostly plays again with half sounds and no background music.

THINGS I HAVE DONE:

CPU rebuilt after trace short caused a major Pinbot meltdown. (some Scoreboard LEDS went amazingly bright during meltdown)
Scoreboard driver board rebuilt after trace short
All fuses checked
All power supply voltages dead on
All molex connectors and pcb edge conectors cleaned and reseated.
I adjusted the volume pot to try and get rid of the speaker crackle. No change except volume of sound and backgroung crakle normally vary with pot position.
Any ideas???
 
(one problem at a time)

Swap score displays for P1 and P3 to see if the problem follows the display or stays with the wiring harness.
 
Back
Top Bottom