Skip to main content

I have a PS2 3v processor board with some issues that have me stumped.  

Symptoms are:

The sounds decreases in volume about 2 seconds after it starts up.  

The motor will not change directions but the headlights do



Things I have changed:

Relay K1

Audio Amp U5 (board originally had no sound)

U4 (board was originally non responsive)

Q19 (was burnt)



Any help would be greatly appreciated!

Last edited by David Minarik
Original Post

Replies sorted oldest to newest

Considering the damage you had be careful with the test a new power board may smoke Q-19 again.

There is a Fet that controls relay.  I never have changed  a relay on a 3V board.

BUT the critical issue is the volume.  While battery charging and such is done on the PS board, the processor directly controls those chips.  If the processor took a hit you can't fix it.  Are you testing with DCS or conventional, will it play shutdown sounds when power shut off.  G

Alan, Jon and George,

Thank you for your input!  Here is more info:

  • Alan, The reset did nothing.
  • Jon, The Power board seems to be OK.  I tried a new power board and got the same results.  I also tried this power board with another processor board and it worked fine.
  • George, The relay does not click when powered up. Do you happen to know what FET it is that controls the relay?  Do you know what processor chip that might be?  I can try to pull one off of a donor board with hot air.
  • I am testing on a PS2 Test Fixture and it does power down ok when shut down.


It seems I might have gone too far down the rabbit hole on this one.

I am sorry, you said Q-19 smoke and I was thinking Q-23 on PS.  So sounds like battery circuit is fine?  Again, conventional shut down works, not DCS shut down.  Only way to ensure battery circuit works. 

Q-10 is the relay fet same part as light fets.  I have a half volume board on the bench.  Relay, and half volume can be loss of trace internally, damaged processor.  Don't remember which one by number just sight.  I traced the battery signal to it along time ago.  Your talking the large processor chip with 4 sides of legs.  Good luck on that one.

Can't fix them all, but I love your effort:-)  G

@Alan Mancus posted:

by the time you heat the processor chip to remove a old good chip you will have destroyed the process ic and then the chip is shot anyway!

A hot air tool is what many rework shops use to remove and replace the large chips.  If you have a full setup, you have a set of nozzles that direct the hot air right to the leads and not on the chip body.

Attachments

Images (1)
  • mceclip0

Well I have given up on this board.  I replaced Q10 with no luck reviving the relay.  

i was able to remove the MTH chip pretty easily with very little heat.  I used some low temp solder and a single tip on a hot air torch.   It came right off.

I would imagine that most of you are using a microscope.  I finally got one and was able to repair about a dozen boards in the last two weeks.   I wish I had one years ago.   What a game changer!

Something else I wish I had years ago are the replacement pads/trace sheets.  Another game changer.

Thanks to all of you who offered help it was as very appreciated!

Add Reply

Post
The DCS Forum is sponsored by

OGR Publishing, Inc., 1310 Eastside Centre Ct, Ste 6, Mountain Home, AR 72653
800-980-OGRR (6477)
www.ogaugerr.com

×
×
×
×
Link copied to your clipboard.
×
×