The DCC controller arrived today.
As you have not said whether your Hornby Select purchase was a 'Brand New' Select or a previously owned one. Knowing the firmware version of the Select may have a bearing on your issue as written.
So to help us decide whether the firmware level may or may not be a contributory cause of your issue, can you please tell us the very first number to appear briefly on the Select LCD screen when you power it up. Expect to see a number between 10 & 20.
However, regardless of the firmware revision level of the Select, your issue cause might be more basic.
You say that the 'Lights are on'. Normally with a DCC fitted loco, the lights won't come on until they are switched on with a DCC F0 command. The fact that they are on, just by placing the loco on the track, infers that the loco might possibly have faulty socket wiring. Ignore this statement if you did actually send the F0 command to switch the lights on. Even if you didn't send an F0 command, send one anyway to see if the lights go off.
For the lights to come on or go off with the F0 command, then you must have selected the correct DCC address of the decoder first. If then, the loco is still not moving, then it [or the decoder] is probably faulty.
Check this out by reverting the loco back to 'DCC Ready' by removing the Rails decoder and re-instating the 'Blanking Plate' then test the loco on a new fully charged 9 volt battery. If the loco motor still doesn't turn with a battery across its wheels, then the loco is faulty, if the wheels turn then it would seem to indicate that your Rails decoder is either faulty of not compatible with the Select controller. This brings us full circle to the first question regarding the firmware revision level of the Select. Early version firmware Selects may have issues with non Hornby decoders.
Even with later firmware revisions, some rogue budget decoders may still have problems. You haven't given much detail about this 'Rails' decoder. Such as what decoder brand is it based upon, I would imagine that Rails of Sheffield will have badge engineered somebody else's decoder or bought in a cheap clone from China. Either way, the solution might be purchasing a better well known branded decoder.
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