Here is a way to add a functional working rear light to the existing casting on the Intermountain FP7.
UPDATED 11-26-06 This light will work in DC and DCC
Objective: create a functional rear light by adding an LED to the existing QSI decoder
What you will need:
1. Ngineering Part Number N1022-2 2x3 Super-Incandescent LED http://www.ngineering.com
2. 9-pin DCC Decoder wire harness with JST connector such as a Digitrax DHWH
3. Dremel Tool with #194 metal cutting bit or similiar
4. Snap Saw
STEP ONE:
Remove couplers and body shell per Intermountain instruction sheet. For the following refer to the above photo.
Remove the speaker mounting bracket, speaker, rear truck and coupling linkage.
Use a Dremel Tool with the #194 bit to cut a notch in the rear of the locomotive frame approx. 3/32 inch from left rear edge, and 7/64 inch deep at top edge of the frame. Square up notch and check LED for clearance.
STEP TWO:
Cut 4 pin section from 9-pin wire harness using a snap saw. Plug into socket on QSI decoder as shown below:
Leave enough wire on the harness to solder the LED to the wires as shown in the top photo. Note the above photo for the following:
LED POSITIVE (ANODE)connects to the RED wire; LED NEGATIVE (CATHODE) to the GREEN wire.
STEP THREE:
Install the truck and linkage, and speaker. Route the harness and LED under the speaker bracket as show in the photos. Do not install bracket screws at this time.
STEP FOUR:
Line the notch with a piece of Kapton tape or similar. Install the LED in the notch as shown in the photos. NOTE: make sure the LED's solder connections do not touch each other or the frame. A spot of GOO or Ambroid flexible glue will hold the LED in place.
Install speaker bracket screws.
Verify that the new wires do not rub against drive linkage. Check the locomotive for operation. The rear light will come on when reverse is chosen and the throttle is NOT at zero (loco in motion). When the locomotive comes to a stop the light in on for approximately 5 seconds, then goes dark. Reassemble locomotive when finished.
Enjoy!
Carl in Florida - - - - - - - - - - We need an HO Amtrak SDP40F and GE U36B oh wait- We GOT THEM!
Thanks for the information Carl,
Will this backup light function in the analog mode as well?
Mike Sowsun
msowsun wrote: Thanks for the information Carl, Will this backup light function in the analog mode as well? Mike Sowsun
Mike,
I'm happy to report it works in DC mode as well! Thanks for asking the question; I did not think to add it to my opening comments in the post; I'll edit them now. Let me know what you think when you modify yours. The cool thing is this LED is great for headlights, lighting car interiors and other uses for a bright light that doesn't heat up and draws very little current.
Carl,
This is excellent! You should consider forwarding this to the MRR staffers as this would be a great article they may want to post in a future magazine issue.
Is this procedure similar to what can be done with P2K E units?
"I like my Pullman Standards & Budds in Stainless Steel flavors, thank you!"
This is GREAT! I can't say that I will probably use this particular clinic, but I am so glad to see it. Personally, I would love to see much more of this type of activity on this forum. This is the whoe reason I joined this site in the first place. This is real, helpful modeling info. Thank you for offering it.
Ron
Owner and superintendant of the N scale Texas Colorado & Western Railway, a protolanced representaion of the BNSF from Fort Worth, TX through Wichita Falls TX and into Colorado.
Check out the TC&WRy on at https://www.facebook.com/TCWRy
Check out my MRR How-To YouTube channel at https://www.youtube.com/c/RonsTrainsNThings
Carl
Thanks for the great article and pictures / MINI CLINIC
This is what makes this forum so great.
Keep up the good work.
This is a great little mini clinic. I added reverse lights to my three Intermountain Ontario Northland FP7s using the info here. I also programmed the following CVs to get the light effects listed below. The CV changes below will only work with the Version 7 upgrade chip and not with the chip the loco was shipped with ( Version 6 ).
CV49 to 70, CV50 to 1, CV55 to 170. This lets the F0 key ( headlight master on/off ) turn the headlight(s) on and off. Once the headlight is turned on with F0 it will remain on in foward, neutral forward, reverse and neutral reverse.
Cv49 to 73, CV50 to 1, Cv55 to 165. This lets the F0 key turn the rear light(s) on and off. Once F0 is set to ON the rear light(s) will be on in neutral reverse and reverse. It will go out when the loco is set for neutral forward or foward.
CV49 to 70, CV51 to 0, CV55 to 160. Then CV49 to 73, CV50 to 0, CV55 to 160.
This allows the headlight and reverse light(s) to remain off during sound startup ( lighted number boards will still come on during startup ). The F0 key will turn them on after startup ( reverse light still only comes on in reverse with F0 key toggled on ). If the F0 key is left on during unit shut down the headlight ( and reverse light if the loco was left in reverse during shut down ) will light for a second then go out during the next startup. The F0 key will have to be pushed a couple of times after startup to turn the headlights back on.
Wayne Reid
Ontario,Canada
Thanks folks for the kind comments! Thank you jjjwar for the added information for programming; I posted the information prior to the version 7 release and did not think to update it, so I am glad you did.