R3383TTS Sound but no longer movement

[Geoff G]

R3383TTS purchased new 16 months ago. All sound functions still working normally, but loco will no longer move. Planning to remove tender body to inspect wiring connections, but disappointed to discover that instruction leaflet supplied with loco shows (in Fig.11) a different tender construction to that of model, with securing screws in completely different locations. Any advice would be appreciated.

[96RAF]

Service sheet 346 doesn't show any screws holding the tender body on so it must be one of those where you press the sides together to release locating lugs. Careful with the rear end buffer details which may be attached to both body and chassis.

You may wish to try a decoder reset by writing value 8 to CV8.

of interest does the loco respond if you turn it round on track to face the other way or you can reverse the track feeder wires from the controller. This may seem odd but there was a batch of TTS decoders that were uni-directional both for programming and control.

[Chrissaf]

If you purchase a spare Hornby X9958 four pin socket and add a pair of wire links as shown in the schematic below, then you can test the loco wheel pickups and motor on a DC Analogue power supply or a reasonably large battery with a battery voltage between 6 and 12 volts.

If the wheels don't turn when using this DIY made bypass connector then the issue is in the loco and could possibly be a faulty motor or wiring in the loco.

If the wheels turn on a DC supply whilst using this DIY made bypass connector, then you know that the issue is in the tender, which could be the TTS decoder output H bridge motor control circuit OR the motor wiring between the tender socket and decoder. It is unlikely to be the wiring between tender wheel pickups and decoder as you say the sounds work.

[Geoff G]

Thanks to both 96RAF and Chrissaf for your prompt responses.

With reference to 96RAF's response, I omitted to mention that I had already tried both a decoder reset and turning the loco to face the opposite direction: both to no avail.

On the issue of the tender body removal, the instruction sheet supplied with the model is numbered 4/1361E, wherein Fig.11 shows two assembly screws just ahead of the front pair of wheels; Fig.12 then shows the chassis being eased down at the front and pulled forward to disengage at the rear. The model itself, on the other hand, has two assembly screws between the middle and rear wheels rather than at the front. These screws release the rear of the tender body from the chassis very easily, but there is no obvious means of release at the front. Indeed, the very fine vertical handrails in each front corner appear to be fixed to the body at the top and the chassis at the bottom!

In the hope of avoiding removal of the tender body, I will follow Chrissaf's advice and avail myself of a spare X9958 four pin socket to help determine where the fault may lie.

[ColinB]

What it might be if it isn't any of the one Chrissaf mentions it might be the four pin socket in the tender, The socket is connected to a PCB. On one of my locos the track was broken between where the wire solders on and the connection to the plug. The other thing that also happens is the pins move backwards in the plug, meaning that individual pins don't connect properly. When you inspect the plug, check for any broken bits of plastic also broken or bent pins inside the socket. On my loco not only was the track broken, but the pin had come out of the plug.