Arcade Tech and Repair, Bally/Midway, Repair Logs

Alltek Ultimate Solenoid Driver Board with only the +43 VDC LED lit

So I have a stand-alone Mata Hari headboard that is used for testing purposes.

I previously had a Alltek Ultimate Solenoid Driver Board (USDB) in it that was powering an Alltek MPU board.  That USDB was pulled because it was needed for another purpose and I later received a new USDB as a replacement.  However, after connecting this one up it only lit up its +43 VDC LED. (Actually, it also lit up its 180 VDC LED, but that has nothing to do with this post.)

USDB Not Powering Up Correctly
Not Powering Up Correctly

I verified all of the voltages on the power supply’s (rectifier board’s) test points and all the way to the back of the connector that plugs into J3 on the USDB.  Everything was where it should be.  I even resocketed and replaced the plug for the J3 connector on the power supply, just in case (some pins showed signs of burning), but that did not fix anything, either.

I looked around Alltek’s web site but did not find anything for the specific issue I was having.  I sent an email and quickly got a response from “Dave” offering to replace the board, no questions asked.  I realized I had not described the problem correctly and after I did, he quickly identified the problem as a missing +12 VDC going into the board as that is what the +5 VDC and +3V3 rails derive from.

I was a bit skeptical as I had already verified that the +12 VDC existed and went to the connector but told him I would take another look at it.  Having a closer look at the connector it looked like the wiper on the orange +12 VDC wire had backed out of the connector a bit.  I pulled it from the connector and it disintegrated as it came out.  I think I found the problem!

I clipped the broken wiper, crimped on a replacement, and reinserted it into the connector.  Upon applying power the USDB came right up with all of its LEDs lit and the tornado was, well, tornadoing.

USDB Powered Up Correctly
Working Once More!

So!  Just because you have signal or voltage present on the back or inspection/testing side of a connector does not mean that it is actually present on the other side of that connector!

And kudos to “Dave” at Alltek for helping me get things sorted out!