It's lack of sufficient load for the ack pulse on the program track. They might work with a light bulb, bit with an LED, not much of a chance.
Just use Ops Mode. JMRI will still save the settings you pick, even if it can't read from the decoder. Just make sure you have no other loco with the same address on the track at the same time.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Well those bulbs draw too much current. Probably won;t hurt anything ont he program track (but probably won't work, either), but if you tried to turn on a function output on the main with one of those hooked up it would fry the decoder.
Yes, the decoder needs a load to be able to do a read back on the program track. Most motor decoders need something connected to the motor terminals to work properly as well.
Try a 1K resistor across the program track, the ack pulse doesn't need much, and a 1K resistor seems to be plenty to help most decoders that need a little help, like the cheapy Bachmann motor only ones.
Load the track with a resistor - loading it with those bulbs is far too much load. An 1157 bulb is somewhere just north of 2.5 amps. Even with a program track booster, there's not that much current on the program track.
The DCC standards specify not more than 250ma on the program track, and the ack pulse from the decodr should be 60ma minimum. On a function decoder where the functions are limited to 50ma, you're not going to get a full 50ma load. a 1K or slightly under resistor will add anouther 9-10ma and bump it over.
Actually the TL4 and TF1 instructions say the function output(s) are good for 125ma each, so you can certainly contrive a load for programming - a 150 ohm 1 watt resistor would pull 80ma. 1 watt would be the bare minimum - I^2R give.96 watt!
Of course, the instructions make no mention of needing a load on the function output for it to program - and they also do not program in Ops Mode, so forget about that.
You will note I have mentioned several times, I love my Digitrax DCC system but I won't use any of their decoders. TCS and ESU ones are just infinitely superior. Stick with the TCS FL series. They even say right in the instructions to connect a 50-100 ohm resistor between the blue and any function wire for readback on the program track.
I do find it funny that TCS does the same thing Digitrax does - puts some basic setup information in the sheet that comes with the decoder, but refers you to the seperate "comprehensive guide" to learn ALL the features. But no one ever complains about TCS doing this. If you've never looked at that book (free download on the TCS web site), take a look - it's amazing the array of adjustments and features even their more basic motor-only decoders actually have.