PS2 trouble shooting on SD9

1. The rear truck dose not completely straighten out after coming out of a from a curve.

Can't help with this one.

 2.  I have reset the engine back to factory specs. I still cannot get the volume to raise to less than half. My comparison to the sound level is based by side by side with my SD24.

Is this a 5 volt PS2 system (8.4/9 volt battery)? If so, this is a symptom of a failing speaker that needs to be replaced.

 3. The battery was virtually dead, I recharge the battery over night. DCS showed the battery was low. Prior to charging, I unpluged and repluged the battery. I also suspected this was part of the volume issue. When tested this morning same issues.

DCS is showing you the status of the battery charging circuit, not the battery. This shows that the circuit is hardly working because the battery is fully charged.

4. Engine shut down a few time on its own. I checked the sections of track and found no power issues . I suspect that this is related to the rear truck.with it not aligning correctly .

That's possible. However, the culprit is more likely electrical, unless the truck misalignment is causing an  electrical short circuit.

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The ni-cad battery is the correct battery for a PS2 engine (blue)with the 2prong plug. 

For the truck issue, with the shell off you should be able to see how the motor comes through the frame and is connected to the truck.  Manually move the trucks back and forth, with the one you are having an issue with try to determine if it is a matter something binding. for example if there is a bend to the frame perhaps as the motor and truck turn there is a point where the frame is binding  causing the issue,you could remove the motor from the truck and inspecting the frame.  If when you are turning the truck if if it is just "sluggish" perhaps a bit of lube where the truck meets the frame.  ..Just throwing this out there from a rookie

If you do pop the shell, a single screw under the truck and below the motor should release the motor from the truck so you can inspect for a bent frame/chassis or whatever.   The motor and truck "sandwich" the chassis - kind of hard to explain but obvious as you loosen the screw.  The motor will separate from the truck with a little wiggling. The red/black wires going to the screw terminals on top of the truck are of course the roller (red) and wheel (black) contacts.  Sometimes those screws come loose and the rotation of the truck might cause the intermittent electrical behavior in your #4.

If nothing comes from the above, I suppose you could separate both trucks from their motors and swap trucks to see if the problem follows the truck.  This requires disconnecting some wires so if pictures or additional instructions would help, just ask.

As for the volume issue, are you able to power up you engine in Conventional mode?  If so you should be able to adjust the manual volume pot to max.  The volume in Conventional mode set to max should be the same as the volume set to max in DCS.  It would be useful to know if the max volume levels are the same for conventional and DCS (albeit lower than what you expect).

Stan 

I just finished resemble the engine. Took the rear truck apart.

I found that the two wires leading from the pickup roller were touching: Fixed  I  

 I realigned the motor and repositioned the wiring including increasing play with the wire leading from the automatic couple . Truck assembly tracks straight now.: Fixed 

repaired the cover for the front motor( mounts  cracked and broken ) super glue repositioned the wiring  : fixed  

Now getting ready to check the connection to the speaker. 

Now that you have the truck fixed and the battery charged.  Turn the engine on in conventional and see what it sounds like.  Then turn power off and see if shut down sounds play or the engine abruptly shuts off.

Reduced volume if not the volume pot adjustment in conventional can be a sign of a dead battery dragging down the 5V circuit which is what powers the audio amp.

In rare occasions you can have a bad power supply board if battery is good, and in even rarer occasions the processor board is bad.

Same for DCS operation.  If you find the DCS still reporting low battery and the sounds at low volume and no changes stick at shutdown after replacing the battery you may very well have a hardware problem too.   G

If the battery worked in a different engine, and a known good battery did not work in your engine you have one of 2 problems.  Either the PS board (top board) is bad, or the processor board is bad.  You can try swapping in a new power supply board and then see if the shut downs sounds in conventional work.

With this issue, none of the resets will stay, because the battery is not available to complete the memory writing after the reset and power down of the engine.  I have one on my bench right now that behaves the same as yours and it is the processor that is bad.  G

You can contact me via my profile e-mail.  I have them.  What is best is for you to send the boards to me.  I can test them and determine which board is bad.  I am an MTH ASC.  G

From your SD70.  Just kidding.

If you are handy with a DMM and want to poke around a bit more before sending your boards to GGG, there are a couple things you can look at in addition to sniffing around the board for that eau-de-burnt fragrance.  I am curious about the 10 second behavior.  When you say it is louder, is it the loudness you expect suggesting perhaps that the electronics works for 10 sec and then goes limp?

Stan,  What would you test.  Board starts up fine at full sound volume then goes to half volume after start up.  Battery circuit not working so if you shut off power sounds cut out immediately.

In conventional no motion since no battery continuity.  In DCS runs fine but no setting stick, can't do factory resets and retain the setting and volume is still half.

Change power board same symptom, place original PS board in different processor works fine.

Changed audio amp on processor, no change.

So what do you test?  I can tell you the 5VDC buss has normal static readings, the 3.3VDC buss has normal static readings, but obviously when powered something is effecting the processor board.

Best I could get out of MTH was they have seen bad DSP do this.  Which effectively means the board is dead.

GGG and Stan 

What you just descibed is now what the engine is doing. It will run in DCS only. Before after the battery changeat least it was not drpping out of DCS. I charged the battery over night. When I put the engine on the track. I had to reprogram the engine into DCS. As long as there is track power, engine dose not drop from the system . To ensure that the battery is not the issue, I am going to buy a fresh battery. About a year ago I had a Ni cad battery short circuit after a charge. What do you think?

I would just plug a 6V light into the battery and measure the voltage?  But since the battery worked in another engine or another battery didn't work in this engine it is not the battery.

Let see what Stan thinks we should test with a DMM, but I have a board on the bench doing the exact same thing.  As I said in the e-mail, it is either a bad Power Supply board or a bad Processor board.  Stan what do you want us to test??  G

It appears there are two conversations (engines) going on here.

SD45.  My guess is you have a faulty Power Supply (smaller top board). My suggestion was to use a DMM to look at the 5V supply with a DMM.  I only suggest this because you seem to be a hands-on DIY - otherwise just send it to GGG for repair.  Attached is a photo of one place to measure the +5V supply line.  You need to be careful not to short anything else but here's a short video showing what happens when you apply and remove track voltage.  Note you can see the green lock-on light indicating track voltage is present, you can hear the diesel engine sound, and you can see a cab light.  The key is when track power is removed, the 2xAA cells generate a boosted voltage of about 4 Volts.  This 4 Volts (rather than 5V) is, in part, why the audio volume drops when track voltage is removed.  The 5V supply powers the audio amp chip and if it only gets 4V the volume drops.  Do you get 5V with track power is applied?  Does this change after 10 seconds (or whatever)?  Does the volume drop coincide with the end of the start-up rev'ing sound reaches a continuous loop?  What happens when track power is removed?  If you have a Z4000 or other method to monitor track CURRENT, what is the track CURRENT doing during those magic 10 seconds when things seem to work?

GGG. Your symptoms seem slightly different.  If you have already swapped Power Supply boards and nothing changes, then IMO you have a faulty Processor board.  If your volume-drop exactly coincides with the transition from the startup rev'ing sound to the continuous idle sound (?) then you may indeed have a DSP problem since the power supply hardware is not correlated with that sound transition.

Stan,  We are talking two engines and I believe both our symptoms are the same.  If you read thru his post his transition to half volume is the same.  Since his engine runs with this reduced volume we know he has good 5V (otherwise the engine would not startup.  Since the sounds stop abrubtly when power is removed, we know the battery circuit is not working.  He used the battery in a different engine and it worked fine.

If the battery isn't dead/shorted, then there is no reason to have sound volume drop without another problem.

The traditional training is that the PS board is bad.  If this is a Rev B PS then the battery circuit parts are obsolete (unless we get lucky with the small SMD resistor).

What I have found is that the processor board also controls the Battery circuit.  Same symptoms, but when I use the PS in a good processor board with same battery the battery circuit and volume work fine.  New PS won't work with processor board.

So I was hoping you had some measurements on the processor board or PS that would indicate if this signal is present or not.  Off course if it is a DSP vice one of the other passive devices or microcontrollers then it really doesn't matter since replacing a DSP isn't going to happen outside of a factory.  :-)

I told the owner a test of the PS board first, followed by the processor.  Validating the symptom via DMM measurements doesn't really advance the troubleshooting in my opinion.  It doesn't distinguish which board is bad. 

What I know is that static reading on the 5V circuit are normal before start up.  After start up and shut down, they are much lower for a period of time.  I can watch the resistance build back up.  Not sure if it is a capacitor discharging, or some other device, but resistance is low and this could be causing a heavier draw on the 5V regulator, or the 3.3V is dragged down and disrupting the processor.  For me it is curiosity and the hope a simpled device can be isolated so the boards can be repaired instead of replaced.  G

GGG, you may be correct that the SD9 and your boards have the same problem but I'm still not reading that the symptoms are in fact identical.  Because if not, I still think it's possible the SD9 can be solved with just a Power Supply board swap. 

You said your volume dropped in half "after startup".   In other words, it appears you can have your board powered up indefinitely in shutdown (DCS mode).  Previously I asked if the volume drop exactly coincides when the diesel revup sound transitions to the continuous rev'ing which occurs at about 14-sec into the video I posted.  If so, then this suggests a software (vs. hardware or power) problem which could be from the faulty DSP chip hypothesis.  And in your case you confirmed the +5V supply is stable even when the volume drops.

OTOH, SD9 initially said his volume was always half expected, then later said his volume dropped "after 10 sec" in conventional.  So I'm not clear under what conditions the volume drops.  As you pointed out yourself, if something drags down the +5V line then the volume might drop.  Hence I suggest he measure the +5V supply voltage.   Since his drop occurs in conventional (unclear what happens for him in DCS), it could be the +5V sags after 10 sec of track power being applied to the hardware (different than your DCS scenario where power can be applied for hours as long as its in shutdown).  Since the "20 questions" game gets tedious and boring to the non-enthusiast, perhaps SD9 should just send his boards to you.

So back to your board.  With all other engine settings and conditions unchanged, if you start with a volume of half (rather than full), does the volume drop to a quarter (rather than half) after the same chronological time, at the same point in the revup sound, or none of the above?  Have you already re-loaded a known-good soundset?  I understand your sounds cut-out immediately on power-loss but are you sure you don't have two separate problems?  Does your DSP part number begin with TMS24... or MTHS...  If the former, these are Flash-memory DSP chips which can be re-programmed (given MTH told you it is likely a bad DSP chip) without chip removal but maybe that's something only certain MTH repair centers can do(?).

Are you saying your idle (non-moving, no-smoke) SD9 is drawing 1.7 Amps at 16 Volts...and that turning on smoke adds a full Amp (+16 Watts of power)?!

Hangup and immediately dial 9-1-1.  Seriously, please confirm those numbers.

That was moving 8137376432

Doug, can you make the +5V measurement as shown in the video?  If not, visually inspect and sniff around your boards and if nothing stands out then make arrangements with GGG to have him look/fix them.

Perhaps my OCD fascination with +5V is not clear.  GGG's board apparently has a solid +5V as long as the engine is in DCS shutdown.  Note that when in DCS shutdown the processor chip (aka DSP) is quite busy - decoding DCS track communications waiting for a magic command to startup.  In fact, when in shutdown, the processor can be running motor control algorithms in so called "stealth" mode.  So the processor is running, executing instructions, and drawing probably as much power as when the engine is started up.  The question is why does the +5V supply line sag when, or soon after, the sounds start?  If the sagging is reduced if you turn down the volume, perhaps there's a short or something untoward in the speaker path.  You might try lowering DCS volume before starting up the engine.  You might run in conventional so that the manual control sets volume (since you can't save DCS volume settings right now).  You might disconnect the speaker to see if you can retain DCS settings (albeit losing the ability to "hear" the 6-7 sec shutdown sound).  What if you activate the Horn which probably draws the most power of any audio sound?  Many things to try if you're the curious type!

I think if you solve the +5V sag problem, you might solve the battery problem for free since the functions are very closely related.  In short, if something is dragging down the +5V supply during normal operation powered by the formidable Z4000, why would you think a dinky NiCd battery could supply enough +5V power to run shutdown sounds, save DCS settings, etc?

This is why I think monitoring the +5V supply under various conditions is a useful troubleshooting tool.  Just my 2 cents.

Are you saying your idle (non-moving, no-smoke) SD9 is drawing 1.7 Amps at 16 Volts...and that turning on smoke adds a full Amp (+16 Watts of power)?! At Idle draws 1.4/5 amps at 16

Doug,  Your symptoms are similiar to mine.  Since you are competent and have the SD-24, you can swap PS boards.  If the SD-9 runs fine with the SD-24 PS then the PS board was bad.  If not, then most likely the processor board was bad.

You also can try to run the SD-24 with the SD-9 PS board.  If the SD-24 runs fine you have confirmed the PS board from the SD-9 is good.

In my case I swapped in a new processor board with the original PS board and the engine ran fine, so there was no issue with harness, speaker, etc.. which I always check.

Even operating in DCS the engine runs fine, just reduced volume.

What I was hoping to get from Stan (since he seems to have intimate design level details) was confirmation of a bad DSP or a specific component to check.

For your case, you have enough information without reading Voltages to conduct the isolation trouble shooting.  I can call you and walk you through if you want, I do that for my customers.

I think you can isolate this which save having to ship an engine.  G

Stan, I appreciate your insight, but how do you know there is a sagging 5V?  If the 5V sagged sufficiently wouldn't the 3.3V regulator shutdown?

The 5V regulator is only a 1amp regulator, the battery can certainly source that until Q-23 blows at 1.7amps or so.

In my case I transfer the boards and test on the bench with the tester so that eliminates the engine hardware.

Swapping PS on to the bad processor did not work, yet both PS worked with a good processor.  The revelation was that a signal from the processor seems to activate or deactivate the battery circuit on the PS board.

Do you know what component on the processor signals the PS Battery Circuit?  G

I just powered up a PS2 SD45 in conventional at 16V and the Z4000 says 0.3 Amps at 16V.  This is with 3 bulbs on, sound rev'ing at Idle, non-moving, smoke off.  So if you are measuring JUST the SD9, then you have over 15 Watts of power going somewhere.

Again, if don't want to go down the 5V supply measurement path, that's fine. You should contact GGG who has a specific plan of action for your engine.  I'm just trying to put ideas out on the table that might (or might not) help other OGR readers troubleshoot their PS2 engines.  I have found that simple voltage and current measurements and thinking about how much and where the power (Volts x Current = Watts) is flowing is a useful troubleshooting tool.

Because you said, "static reading on the 5V circuit are normal before start up.  After start up and shut down, they are much lower for a period of time."  What the video showed was that sagging to ~4V when powered by the battery must be OK since the shutdown sounds still play, the processor saves DCS settings, etc.  Thus, the 3.3V regulator must still be functioning.

It appears your audio volume drops because the +5V supply drops. We know the volume does not drop for a working PS2 engine.  So something is dragging down the +5V supply.  So my approach is to first find the cause of this sagging and later track down why the battery circuit does not kick-in when power is removed.  I realize you are using some kind of test fixture outside of a chassis so how many things could it be?  I get that.  If there is some adjustment (such as the volume) or configuration that changes the amount of sagging, that might help isolate the component.  Of course if it is some component(s) on the processor board related to the battery circuit that is dragging down +5V, then it's a challenge.  Perhaps this is why MTH suggested a bad DSP which would be such a component.  This is just my opinion.

"The number you have dialed has been disconnected or is no longer in service..."

When Dcs first came out we used to exchange sound files long before they were available from MTH. Anyway I had one engine so screwed up that the only way to get it from making a white noise sound  was to pull the battery. It wouldn't shut off

The fix was a reload of the sound file. Applicable here? Is there something in the sound file that regulates the battery function??

Before you jump all over me, I know nothing about fixing circuits on the boards however swapping boards is not that difficult. Did you try swapping boards ? if so what board is not functioning?

Is the battery circuit supose to deactivate after the start up  sequence  ends? 

Doug,

If you do choose to probe the +5V supply line as in my earlier video, GGG brings up a good point about probing in close quarters.  One thing you might do is insulate the long metal probe tip with heat-shrink or some stripped-off wire insulation as illustrated below.

Note that the measurement I made requires two hands just to probe the circuit so you might need an assistant to actually switch on and off track power.

If you do choose to swap power supply boards and have never dis-assembled a PS2 diesel before, here's a link to a post in with a video showing roughly what's involved in removing the boards from the chassis.  If you're only swapping the top board you may not need to remove everything as shown but I think it helps to see all the pieces.  There's probably a better how-to or video or instructions on this but this is all I am aware of.  When separating the two boards be very careful and try to lift the board straight up as the gold interconnection pins are somewhat bend-able and they of course must mate exactly when re-installed.

https://ogrforum.com/t...18#16071832993945918

Also, carefully monitor the Z4000 current.  Since you have baseline measurements on your SD9 and SD70 you should expect numbers like that.  If not, immediately remove power.

Doug,  The battery circuit should remain on as the battery is charged, and also available in conventional for continuity of power.

Stan, I took your readings and I also took the battery circuit readings.

What was interesting is that as soon as the board is powered up the Battery voltage dropped from 2.4V to .5Vs, but the 5V circuit remained at 5 VDC even after the audio volume dropped off.  I was measuring the battery voltage at the charge port.

What ever the fault is, it is shorting the battery out, but not the 5V regulator.  Once power is removed the battery voltage came back up to about 2.2 to 2.3 V and then slowly climbed back to 2.4Vs.

Some where there must be an independent connection of the battery circuit that has an effect on the audio amp but not on the smoke fan, LED circuit or the 5V regulator itself.  G

Looking at Stan's picture, the first is the +5V, the next 2 are Positive Voltage from the output of the FWBR, 4th is a logic signal from the PS board, and the last 2 are the PCB Ground or negative of the FWBR.

I believe (my opinion) you are safer swapping the PS boards and see if symptoms move with the PS board or remain with the processor.  G 

A charged good 2.4V NiCd has such a low internal resistance that reading 0.5V at its terminals means Amps of current are flowing.  That would make me nervous as presumably that is flowing through component(s) of the Power Supply board.  Based on your board swaps, it does appear to be the Processor board possibly giving conflicting-signals to the Power Supply board about charging/discharging or whatever.  Your point about Easter Egg hunting on the Processor board is well taken; aside from an educational endeavor, it seems a new Processor board is the next step.  This is nothing you haven't already stated.

Couple irrelevant questions.

1. What kind of engine did your board come from?

2. If you activate the Horn immediately on Startup, presumably the Horn sound also drops... but does is hasten the volume drop?

3. If you run without a battery, does anything change wrt to audio volume drop?