8 pin wiring

[guy57]

Hope someone can come to my rescue here! I have a Bachmann 4-6-2 light Pacific DCC w/ sound NYC 4552. One of my helpers? decided to try and repair the harness and in the process tore all the wires from the connector. This is a fairly new loco, so is there a way to get the pinout of the connector from the factory or am I going to have to try to  read all the connections coming from the loco? If that is the case, what should the motor read in ohms and how can I distinguish the + and common of the light. Also, is there 1 contact that is not used? Any and all help would be greatly appreciated

Also, is pin1 on the left or right?





Squirls b crazy

[rich1998]

There is no wiring here. Bachmann does not post them the last I knew.
A couple people posted diagrams they traced some years ago but you would have to search. I never bookmarked the pages. Sorry.
A motor will be under a hundred ohms. A light bulb probably also but an LED max resistance so not traceable with a meter. I have tried. Use a nine volt battery and a 1k resistor for an LED. The LED is polarity sensitive. Switch leads if one connection does not work. The PC board is labeled to start with.
THe two pin connector is driver pickups. Four pin, two for motor two for light so quite sure an LED.
Good luck.

Edit. Jonathan is into his 2-8-0. He might help.

Rich

[grsman]

Hope someone can come to my rescue here! I have a Bachmann 4-6-2 light Pacific DCC w/ sound NYC 4552. One of my helpers? decided to try and repair the harness and in the process tore all the wires from the connector. This is a fairly new loco, so is there a way to get the pinout of the connector from the factory or am I going to have to try to  read all the connections coming from the loco? If that is the case, what should the motor read in ohms and how can I distinguish the + and common of the light. Also, is there 1 contact that is not used? Any and all help would be greatly appreciated

Also, is pin1 on the left or right?





Squirls b crazy

I am not familiar with this loco. I don't know if the sound board is in the tender or the loco.
The following two references may be of help if you can get to the sound pcb.
They identify all the wires. I don't know which board your loco has. That should be easy to identify.
https://www.bachmanntrains.com/home-usa/dwg/dwgs/HOSoundDecoderInstallation_30mmx24mmx8.8mmboard.pdf
https://www.bachmanntrains.com/home-usa/dwg/dwgs/HOSoundDecoderInstallation_40mmx27mmx7.2mmboard.pdf
This should give you the info you need.
Tom

[Gearedenginefreak]

Here is how I approach unknown wiring.  Use a multimeter and set it on ohms / continuity.  Find the track pickup wires by putting one probe on an unknown wire and one probe on the fireman side pickup wheels. Move from unknown wire to the next until you find the one that reads zero ohms or sounds your continuity buzzer. Then do the same for the engineer side pickup.  So now you have 2 wires identified. Next, get out a 1.5 volt battery (for 1.5 volt lamps to not burn out) and jumper to any other 2 unknown wires and look for lights to go on. Be sure to swap leads on the battery in case it is an led and you have polarity wrong. If you get no lights, try a 3 volt battery doing the same thing as above. That will nearly always get the lamps identified even if very dim (incandescent).  LEDs with 3 volts will light brightly unless they have inline resistors.  Be sure to repeat this until you find all the lamps - forward, reverse if applicable, cab lights if applicable, etc. Thru the process of elimination you can identify the function common.
Be sure you identify all the lamps before you proceed with a higher volt battery as in the next step - if you dont, you could blow lamps with the 9 volt battery.
After you have found the pickups and the lamps, you can confirm the motor with a 9 volt battery and determine polarity by swapping leads.
You might even find the motor with just the 3 volts.
It took longer to type it out and explain it than it does to actually do it.
I have been able to positively identify my loco wires using this method every time I needed to.
Some manufacturers who I detested their on board decoders had no documentation as to the wiring and also the wiring colors are never to be trusted. I found many factory fresh locos with completely non standard color coding. They just used whatever they had on hand.

Hope that helps,
Tom Wilson

[rich1998]

Yes, I forgot some do not have a meter or the 1k resistor for using a nine volt battery. I keep forgetting I have many years of electronics experience. The previous response is very good.

Just in case, here is the diagram. No wiring info.
Once in a while a diagram will show an eight pin socket with a DC adapter.
https://www.bachmanntrains.com/home-usa/dwg/dwgs/H844X-IS00.PDF

If you need the wires and plugs. I am assuming the plugs were cut off and splicing will be difficult. Don't ask me how I know.

https://estore.bachmanntrains.com/index.php?main_page=index&cPath=68_665&zenid=6psts7k4l5flvd9t0q9c9a23r2

On all my Bachmann locos, the PC boards in the tender are clearly marked. The one that was onboard sound had one PC board that was the SoundTraxx decoder . The other was equipped with a eight pin socked that the decoder plugged into and marked for the wires from the loco.

My DCC ready had a PC board with an eight pin socket that I would plug a decoder into and was marked for the wires from the loco and the pickups from the tender.

I believe the steamer diagrams are pretty much similar for many of the tenders.
Remember the NMRA wiring standard. Only seven wires. Ok, add two for the speaker.

Rich