I have a Bachmann HO 2-6-6-2 articulated loco with a Vandy VC12 tender with DCC (no sound). I want to remove the existing pcb and install a Digitrax SDH166D decoder and wire it directly to the wires coming from the loco. Unfortunately, the 6 wires coming from the loco are all black. Looking at the rear of the loco, the left 4 wires are in one plug and the right two are in another plug. The left two are for the motor, the 3rd shows “D-”, the 4th shows "L+, the 5th shows “L” and the 6th shows “R”. Other than the motor wires, what are the others for???
Two pin connector is for driver pickups. Get your multimeter out and verify continuity.
It is a simple solution to unplug the present decoder from the socket. Get a nine pin to eight pin adapter and plug in the Digitrax.
I believe the loco has LED’s. At least that is what the diagram shows at the Bachmann forum.
Check the PC board for resistors connected to the wires used for lighting. All the components are labeled as I figure you know.
Rich
Spend the extra $5 street price and get the SDXH166. The SDH166 is the same old 8 bit sound. The SDXH166 is 16 bit sound and a vast improvement over the old Digitrax sound decoders.
–Randy
My current setup has the 9 to 8 pin harness but with the original PCB, the decoder, the power extender module and the speaker, I ran out of room in the tender. Soldering the 9 pin harness to the loco wires will free up much needed space. If the two pin connector is for the track pickup and the 1st 2 of the 4-pin connector are for the motor, the remaining 2 must be for the forward light. Thanks for your help!
Some additional informaiton that may be helpful: On the 4-pin Bachmann plug, the two outer wires are motor; the 2 inner wires are the headlight on MOST models. I have ran into some exceptions, which may have been mistakes at the factory.
I finished wiring it today and all functions work perfectly. The D and L terminals were for the forward LED.
what is the difference between the SDH166D and the SDH116? i saw the sdh116 on youtube and i want to know if this was a typo or if it is real. if so what is the difference?
There is no SDH116.
–Randy
On their installation site pages TCS warns about this issue with Bachmann wiring not being consistent neither for pin outs or even wire colours!
Thank you! just made sure i was getting a decoder not somthing else