DCC loco running slow


F

fcwilt

Active Member
Hi,

A DCC equipped loco which had been running fine, today would only run very slow. All functions worked. All driven axles were rotating. It still responded to different speed settings from standing still to this now very low max speed.

According to an online document I found for this loco I performed a decoder reset and it did seem to do a reset. I checked a handful of CVs and they are all back at the default.

Everything seems to be working except the loco's max speed is maybe a 1/3 of what it was.

Any ideas?

Thanks!
 
Some of the newer decoders have a switching mode which turns down the top speed for switching operations. I haven't used it my self and haven't looked to see if the decoders I have offer that feature. but, that's were I would look.
 
I had read about the switching mode but I had no documentation indicating that feature was part of this decoder. I figured that if it DID have the feature doing a decoder reset would turn it off. But the reset made no difference in the speed. I think maybe the h-bridge motor driver in the decoder may have gotten partly fried.
 
I've got a dozen or so decoders one of which I can use for testing to determine if the problem is in the decoder or the drive train. But this was a entry level SoundTraxx Tsunami Sound Decoder and I have no other sound decoders - easy enough to order one though, once I verify where the problem lies.

So much to do - so little time!
 
fcwilt said:
But this was a entry level SoundTraxx Tsunami Sound Decoder and I have no other sound decoders - easy enough to order one though
Click to expand...
I don't know what brand of decoder this was (well I do know it was not Loksound), but I has a sound equipped loco that was consisted with 5 others. I was using the short whistle feature, button F9, to help blow good grade crossings. Suddenly this one loco started dragging. The wheels were still turning just not the same speed as the other units. I tried re-selecting the loco, I tried tipping it off the rails to do a power reset, I tried resetting the controller to 128 steps and then back to 28. All to no avail. Fortunately the museum runs enough power on the point to pull the train even if one units fails so I ended up dragging the slow unit through the entire layout and back into staging.

Then I learned from the Museum's Supervisor of Locomotives that I must have double pressed F9 (F9 F9) in quick succession, and that is what put the unit into what I called "limp mode". A simple F9 again cleared the condition.

However, I just looked at a SoundTraxx Tsunami manual and it says F9 is unassigned. ?? But who knows. Try an F9 and see if it clears the issue.
 
You must log in or register to reply here.



Back
Top