# LGB Coke F7 with Circuit Board Issue



## LGBTA (Nov 11, 2010)

I have a LGB Coke F7 29570 A unit with a power issue. It will run for about 3 minutes then just stop. Lights all still work. Sound in the B unit goes to idle mode. But the A Unit will not do anything else for about 24 hours... Ideas? Does anyone have a spare F7 A unit circuit board with MTS? ANY HELP would be appreciated!


----------



## Dan Pierce (Jan 2, 2008)

Many locos that come with MTS use the same boards, they just have different connectors soldered to the board and different CV settings. 

Steam engines have the CV set for 5 volt smoke an a F key, a diesel would have a flashing light on the same place, just a programming difference. 

Both motors are run in parallel on LGB diesels so it must be a part on the MTS board heating up and not working. 

Does this happen in both directions? 

B unit will go to idle if it is not moving as the sound unit has a sensor on one of the axles for rotation sensing. Same sensor as the Steam sound units for the chuff.


----------



## Trains West (Oct 4, 2008)

have you tryed running it on dc to see if it does the same thing?


----------



## Cougar Rock Rail (Jan 2, 2008)

How many miles has the engine got on it? Maybe one of the motors is worn out and now drawing far too much current, causing the decoder to shutdown to protect itself. Once it's cooled down again, it will run. 

Keith


----------



## LGBTA (Nov 11, 2010)

Less than 20 hours on the unit. Practically brand new.


----------



## LGBTA (Nov 11, 2010)

Either direction. EVERYTHING ELSE remains working EVEN the sound, which obviously goes into idle since it stops moving. Lights stay on, etc... It will not run again for a day or two... REALLY WIERD! I am CONVINCED it is the MTS part of the board. anybody have a board or an F7 I can scrap for a decent price?


----------



## Dan Pierce (Jan 2, 2008)

The sound essentially just runs off track power, it does not get any control from the A unit, just a track power cable(2 wire). 
The 4 wire cable is for speaker control. 

So, only the A unit lights and motors are controlled by the MTS board located in the A unit. 

Are you running analog or digital control of the engine? 

If digital control, can you operate the lights on/off.


----------



## LGBTA (Nov 11, 2010)

Analog... Running off a Control Master 20.


----------



## daylightguy (May 26, 2010)

Contact brigemaster. thay thay a lot of parts from LGBOA. but i would take a look at the motors. if thay sit a lot the grease will
get hard and will put a lot of starn on the MTS decoder a force on the decoder in to shut down

Daylight guy


----------



## Greg Elmassian (Jan 3, 2008)

If it was sitting and would not start up, maybe that could be a possibility. 

But he is running and it shuts down, so grease would be more free, not getting harder. 

But maybe something similar, my guess is a bad solder connection that heats up and opens, possibly in the MTS decoder. 

Greg


----------



## LGBTA (Nov 11, 2010)

I'm with you on this one. Has to be a terminal board issue. At this point I am looking for a board or another F7 with MTS to cannibalize....

TA


----------



## LGBTA (Nov 11, 2010)

Bridgemaster? Can you please tell me more?


----------



## Cougar Rock Rail (Jan 2, 2008)

Can you try your engine on someone else's layout? When you run the engine at your place, how fast are you running it, ie. what % of max throttle? Can you measure the voltage your transformer is putting out? 

Keith


----------



## Madstang (Jan 4, 2008)

SORRY I MISSED THE "ANALOG" I saw you stated MTS that only refurs to the use of the decoders and the central stations, if you are using analog and they have the decoders inside the decoders are passive, and what I origionally posted does not apply....sorry. 

bubba


----------



## Ltotis (Jan 3, 2008)

Saw n LGB F7 for sale at $199 at JAmies Collectables here in Massachusetts. It was modified by the original owner by removing one power block and replacing it with a non-powered one. Not sure if it has MTS.
LAO


----------



## Dan Pierce (Jan 2, 2008)

LGBTA, where are you located? 

If you remove the board, I can check it out for you. 

I have a test jig for testing decoders of any type and I am very familiar with the F7 and LGB decoders.


----------



## LGBTA (Nov 11, 2010)

I see several of you have replied since I last logged on... THANK YOU ALL... 

Here are the answers.... 

Cougar Rock Rail... Test another layout...? Yes I have tried it on all seven of my main lines & the same result happens... Runs long enough to stop on the side of the layout that is hard to get to.... LOL All seven lines have their ON separate and different transformer. All Super Blue OR Control Master 20 Transformers... All in perfect condition. I will have to figure out the voltage testing though... stand by... Although I do not see that being the issue since ALL of my other LGB Engines run tip top on same lines... 

Dan... Send out the board...? I am in Charlotte NC. If you think you can run a diagnostic I will be happy to remove the board and ship it... Please just send me an address and It will be on its way... direct email is [email protected] 

Madstang... MTS vs. Analog...? Yes I am running anaolg, I never got into the MTS stuff. So it would seem to not be a decoder problem but something overheating on the board as someone stated earlier... maybe a solder joint... 

Thank you all again....TA


----------



## Madstang (Jan 4, 2008)

Another thought Klass with Maassoth can diagnos and repair it..or at worst tell you if it can be, and have options if it cannot be.

Below is the web sites dealer contact page. He is located in Cummings GA.


http://www.massoth.de/index.en.html

Bubba


----------

