No coils work on Nitro groundshaker

[paddythegreek]

Sorry for a longish read but
Mate bought a NGS non working. He’s got it up and running but not one coil works in coil test or game play. Ground the transistor tab and the relevant coil fires.
Fuse and holder under playfield are both good. Has replaced the mpu and power supply board with known working ones. There is good continuity between J4 on the mpu and J4 on the psb. The 5v line reads 5.24v. All coils read 43v. I’ve spent a few hours on it trying various things and now I’m at a loss. Anyone any ideas. Ken

 

[pinballmania]

If all the data lines between Mpu and driver board are good then the only thing left if the decoder chip on the driver board or the transistor arrays. Use a logic probe to see if the data is arriving at the decoder and if so then check the outputs.

 

[Jay Walker]

Bear in mind that the 4 'continuous' solenoid drives (including flipper relay and coin lock-out) aren't signalled through the decoder, Ken.

 

[paddythegreek]

Apologies for not putting it in original post but
Flipper coils and coin lockout coils work ok.
Re Andys comment on the decoder chip, 2 replacement psb’s wouldn’t both have faulty decoder chips ( would they). Think I’ll repin the plug wires on the mpu to psb data lines.

 

[astyy]

This happens regular(ish) on my GOLD BALL and is a re-seat the connectors job (which I haven't fixed properly yet).

 

[Jay Walker]

I've just remembered;
Although the 5v line is created on the solenoid driver board, it's supplied to consumers on the board (e.g. the decoder) by a lead in the wiring on the r/h edge of the board. The larger connector, AIR, has a lead between 2 separate pins for this.

 

[paddythegreek]

Guys out today so probably be tomorrow before these data wires get repined. Thanks for everyone’s help. Watch this space

 

[pinballmania]

I've just remembered;
Although the 5v line is created on the solenoid driver board, it's supplied to consumers on the board (e.g. the decoder) by a lead in the wiring on the r/h edge of the board. The larger connector, AIR, has a lead between 2 separate pins for this.

Correct. Can cause problems. You can put this external jumper directly onto the circuit board to eliminate any possible problems.

 

[paddythegreek]

Update. Had about 20 mins whilst guy was busy on grandsons car. Replaced J4-10 pin on cpu and bingo the coils work. Now the damn things resetting, so I presume from the previous posts it’s a 5v issue. Ah well tomorrow’s another day.