TMCC loco runs VERY slow in conventional mode

Would they be K-Line locomotives?  If they're Lionel, how about the actual product number?

I remember this weird behaviour in conventional. You have to turn off speed control, per the attached excerpt from the 2000 SD-90 owners manual.

Rod

to gunrunnerjohn, I found one of the product numbers, 6-28522.

To Rod:  These locos do not have speed control, and that is not really a "fix" now is it..  Turning off something like speed control just covers up the problem.

Using a modern Lionel ZW-L transformer, I have also experienced this condition with a “new” JLC PC TMCC GG1 that I recently acquired from Sidetrack Hobbies. With a Cab 2 controller it runs like a champ!

@Jm posted:

To Rod:  These locos do not have speed control, and that is not really a "fix" now is it..  Turning off something like speed control just covers up the problem.

jm; you can call it whatever you want; I am just using the exact terminology used in the owners manual (from 2000) excerpt that I attached. I recall that once you deactivate speed control per the manual, the engine behaves normally in conventional. In recent years I have been 100% command, so what do I know. Your OP referred to them as "early TMCC".

Rod

Rod is correct. Page 8 of the manual that matches the product number you provided does show it has speed control.

@Jm posted:

To Rod:  These locos do not have speed control, and that is not really a "fix" now is it..  Turning off something like speed control just covers up the problem.

Jm,

The 6-28522 locomotive DOES have speed control.

You've accidentally activated the conventional speed control feature, locking in the low speed.

The procedure that Rod outlined above is correct to turn it off, thereby fixing the problem.

TRW

@Jm posted:

To Rod:  These locos do not have speed control, and that is not really a "fix" now is it..  Turning off something like speed control just covers up the problem.

Au contraire, that model has Odyssey speed control.  It could be having a problem with the DCDS.

@Rod Stewart posted:

I remember this weird behaviour in conventional. You have to turn off speed control, per the attached excerpt from the 2000 SD-90 owners manual.

Rod

I have had this happen as well.  I  have a tmcc loco from early around 2003 that had the same issue.   No problems after getting the speed control turned off.

Let's be fair here.  While turning the speed control off may fix it, that's not really a "fix".  This locomotive should run fine with speed control enabled in command or conventional mode.  The fact that it doesn't indicates there is a problem more than simply disabling an option.

@gunrunnerjohn posted:

Let's be fair here.  While turning the speed control off may fix it, that's not really a "fix".  This locomotive should run fine with speed control enabled in command or conventional mode.  The fact that it doesn't indicates there is a problem more than simply disabling an option.

Well maybe not a fix but if it is incorrectly set in conventional mode, it will never run any faster than where it was set.  Turn it off and then reset it for the desired speed per the manual.

Marty, speed limit and speed control are two different things.  I'm talking about disabling speed control, not setting the speed limit.

I know but this is the issue. Read the manual. It’s the way speed control works in this case.

Thanks for the info.  I had a similar problem a few years ago, and did not have a TMCC system available.  Sent it to the local repair guy - he was stumped and replaced the board.  Pretty sure he gave it an honest effort, based on the amount of time he spent on the phone with me.  I wonder if the speed control setting would have solved the issue.  Sadly, the repair guy passed away about a year ago, so I can't ask him.

When I helped out at the LHS I had 2 of these come in.  Turning off Odyssey in conventional solved the issue.  About a month ago my brother who only runs conventional had the issue and sure enough Odyssey was on.  I understand what John's point is but these older units with Odyssey worked a little odd in conventional.  You were basically setting the speed that you wanted the locomotive to maintain so not matter how much more voltage you gave it, or if the voltage changed on the layout, it maintained that speed.  It's definitely wonky.

Thank you all for your help.  All the email notices of your replies went into my spam folder.  Sorry for not saying something sooner.  I dont use OGR very often as you can tell.  Best regards, Joe.

Joe, did you get your problem sorted out?