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Demco SBS Wireless Coachlink for Supplemental Braking Systems - Braking Indicator System

Demco SBS Wireless Coachlink for Supplemental Braking Systems - Braking Indicator System

Item # SM99945
Our Price: $269.00
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Stay updated on the status of your supplemental braking system. Transmitter installs in your towed car and wirelessly relays information about the car's braking to the monitor in the RV. Monitor with LED and audible alerts plugs into 12V outlet. 1-833-496-1390 to order Demco accessories and parts part number SM99945 or order online at Free expert support on all Demco products. Great prices and Fastest Shipping for Demco SBS Wireless Coachlink for Supplemental Braking Systems - Braking Indicator System. Accessories and Parts reviews from real customers.
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  • Reviews (47)
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Demco Accessories and Parts - SM99945

  • Tow Bar Braking Systems
  • Brake Monitoring System
  • Transmitters
  • Demco

Stay updated on the status of your supplemental braking system. Transmitter installs in your towed car and wirelessly relays information about the car's braking to the monitor in the RV. Monitor with LED and audible alerts plugs into 12V outlet.


  • Braking indicator keeps you updated on the braking activity of your towed car while it's being towed
  • Wireless Coachlink system installs in your towed vehicle and relays information to the receiver monitor
  • Monitor alerts you when the brakes are being applied in the towed car
    • LED light blinks and is easily visible while you are driving
    • Audio tone provides a secondary, audible alert
  • Wireless design allows for quick, easy installation in RV
    • Receiver monitor mounts in RV and plugs into your 12-volt accessory outlet
  • Made in the USA
  • 1-Year limited warranty

Radio Set Graphic

Compatible with most supplemental braking systems, the CoachLink's wireless transmitter and receiver work together to keep you in the loop when it comes to your towed car's braking activity. Simply mount the transmitter in your towed car and the receiver in your RV, and wire the transmitter according to the instruction manual. When the brakes are applied in your towed car, the transmitter will relay that information to the receiver. The receiver will then notify you, using an LED light and an audible alert, so that you can be positive that your supplemental braking system is performing correctly.

9599005 Demco SBS - (Formerly SMI) Wireless Coach Link Braking Indicator System for Supplemental Braking Systems

Replaces Demco SBS SM99945

Installation Details SM99945 Installation instructions

Customer Satisfaction Score:

Customer Reviews

Demco SBS Wireless Coachlink for Supplemental Braking Systems - Braking Indicator System - SM99945

Average Customer Rating:  4.7 out of 5 stars   (47 Customer Reviews)

Stay updated on the status of your supplemental braking system. Transmitter installs in your towed car and wirelessly relays information about the car's braking to the monitor in the RV. Monitor with LED and audible alerts plugs into 12V outlet.


I installed a demco air force 1 on my nautilus and purchase this monitor to replace the dumb lights that stick to the mirror of the toad. The wiring diagram for the coachlink was inconsistent with the wiring on the demco. Stupidly rather than call demco i followed the coachlink wiring. The result was it did not work. Called coachlink. They Pete great and aware of the issue. They replaced the sensor on the actuator no charge. Turns out that the coachlink also fried. I am onnthe road so i ordered a replacement which etrailer got to us. The service eas great just annoyed i had to pay another xxx$ for the second unit


Excellent product offering the ability to easily monitor the tow vehicle brake activation on a monitor right in front of you is a welcome change. Many thanks to Jim D for his idea of cutting off the LED brake indicator plug and butt connecting it to the transmitter. I took Jim's idea one step further and went to my local electronics store and purchased the same kind of plug and wired it to the SMI Transmitter. This way I can still use the LED indicator as a backup if ever needed by simply unplugging the transmitter and plugging it back into the LED. With the new plug I purchased the SMI Red Wire was connected to my new plug's Brown wire and the SMI White wire was connected to my new plugs Red wire as shown in the attached picture. Plugged it up and it worked great. So much simpler than having to splice into the SMI Duo wiring harness.

Thanks for the note. In answer to your question, Yes I still like the SMI dash monitor and it is still working great. Makes it a lot safer seeing right in front of you if your brakes are activated. Thanks
Chuck R - 01/31/2018


Just installed the SMI CoachLink 900 Wireless Transmitter and Receiver Braking Indicator Set in my Honda Fit and Navion Motorhome. Less than 10 minute install to my existing Stay and Play Duo brake system. It just can't get any easier to have a better indication of how my braking system is performing for me from the drivers seat in the motorhome. I added an indicator light in my Honda to let me know that the Duo brake system is active when I turn on my GForce Controller.


I’m thankful etrailer has the parts I need along with easy to follow videos for installation. However, I was disappointed that although the parts were in stock it took a week before you shipped them out of your warehouse.


I haven't installed it yet as I am waiting for a RV repair man to install both it and the Demco Duo Play n Stay. I watched a video on your site and it looked like something a little more complicated for me to do. I am very impressed with etrailer's delivery speed. I was promised for Friday delivery and I got it a day early.


The wireless break indicator unit works well although it is difficult to see the power on light. Installation was a little “dicey” given the small gauge of the wiring but it went pretty smoothly.


Works as described and confirms the braking effects you feel. Lights could be brighter, but worth the piece of mind.


It arrived prior to my deadline as promised. There were no instructions in the Coachlink box but I found them on the web easily enough. I have made three purchases from etrailer and have leaned on them with questions and for technical support. Messages are returned very quickly and they always are helpful. Prices are competitive. I try to order from etrailer whenever possible as they are very easy to work with and are always available with help if needed. Great company and people.

Its been a year since my review and I havent needed any parts from eerailer. My opinion has not changed, they are they are one of the top places I go to for prices and help.
Steve F - 03/23/2018


Great product! I finally broke down and installed this Demco product after numerous efforts to get reliable feedback on braking status from the Air Force One in my toad ... seeing LEDs from the motorhome rear camera and running wires through the wiring connect to a dash light were all sub-optimum. Installing the Demco system was easy, the instructions include wiring diagrams for a number of different braking systems. Once the toad wiring was complete I located the control box where I could see it while driving, plugged it in ... and it worked perfectly! Great peace of mind, I use it as part of my pre-departure check list and glance down to get a confirmation most times I use the brakes.


Easy installation. Simply replaced the LED brake indicator previously installed on the back of rearview mirror with the wireless transmitter supplied with this kit. Transmitter was mounted (using hook and loop tape), directly underneath the SMI G-Force Controller, which is mounted on the tow-kick panel and B-Pillar (besides the driver's seat). Although it appears this location might be in the way of the hood release, it isn't. There is still plenty of room for the hood release to operate on the 2014 Honda CR-V....other models may not have room, but the 2014 Honda CR-V has room. The end is cut off the LED brake indicator and butt-connected to the end of the transmitter and plugged in. The wires were removed from the tie that secured them to the dash (just behind the steering wheel adjustment lock lever) and excess wire was tucked under the carpet, easily accessible if transmitter should need moving later. Receiver activated as expected.


We purchased the Stay N Play brake system with the wireless transmitter, and wish we had done it years ago, instead of messing with the Brake Buddy that we had before. It is so easy now to get our Explorer ready to tow behind our RV, and we like the 'instant' breaking that the Stay N Play affords instead of dealing with the 'lag' that we had in our Brake Buddy. We would definitely recommend this excellent product.


Just what I needed


After towing over 7,000 miles, this works great with no problems. Easy install. I can confirm the brake on tow vehicle is working properly each time I apply brake in MH. Highly recommend for anyone towing a vehicle with active brakes.


This wireless brake lighting monitor works perfectly with my SMI Duo brake assist system. No constantly looking at rear camera on my motorhome. etrailer videos so helpful with entire series of installs on my Wrangler for flat towing.... Tow lights, brake relay, towed vehicle battery charger, SMI Duo system, and this monitor.


Awesome tool for peace of mind that the braking system is working properly when towing. It was very difficult to see the provided light through the rear view camera and now I know immediately when the towed vehicle brakes are applied. Easy installation I did it myself.

by: did a great job getting my order processed and shipped. Although I'm not a big fan of UPS SurePost, everything worked out great this time. The SMI Coachlink wireless device seems to work as advertised. The install was very straight forward. I've been dealing with SMI for several years now. They have always been first rate. No I think if first rate also. Thanks again for the great service.



Excellent product. I use the Ready Brute mechanical brake system hitch. I tow a 2017 Wrangler. This simple to install Coach Link works every time. I’ve used mine for a year now. Just plug it in and boom it works.


The LED indicator for the back of the rear view mirror in the tow car is not always visible, sunlight, glare,etc. This unit makes monitoring the brake system easily visible.


Received product without instructions and package had been opened.
Printed instructions off of web page to install.
Product works great but very hard to see LED in writing of on control box, suggest you place LEDs out side of the writing and increase the brightness.
My wife has to check the lights because I cannot see them during the daylight hours.


The coach link was just what I needed to go with my stay n play brake system. No longer and doubt I my mind when/if the brake activetes


I am very happy with the CoachLink 900. Easy to hook up and use.

Its been working just fine. Still happy with it.
Curt - 12/09/2018


This product is an excellent addition to the braking system. A simple process and installation that allows you tow with confidence. This system allows you to constantly monitor your braking system and alert you to any problems.


As usual, ordering process was simple and efficient. Item was shipped almost immediately and received as promised. I have installed the Wireless Coachlink which was simple with the included instructions and it works flawlessly. I will continue to do business with based on their competitive pricing and superior customer service.


Quick delivery, arrived in good condition. Installation is straightforward. ETrailer is our 'go to' place for RV parts.


Product delivered fast. Connection was easy took about 10 minutes. Display in motor home is dim and hard to see during the day. Demco has a logo label over the led that makes it hard to see in daylight. Have not traveled over the road , so don't know about it keeping connection while traveling

Show More Reviews

See what our Experts say about this Demco Accessories and Parts

  • What is Reception Range of CoachLink 900 Wireless Transmitter and Receiver Braking Indicator Set
    I checked with SMI and the CoachLink 900 Wireless Transmitter and Receiver Braking Indicator Set # SM99945 has a 1/2 mile reception range without obstruction.
    view full answer...
  • Can I Use The Demco SBS Wireless Coachlink With A Demco Air Force One Braking System
    Yes, you can use the Demco SBS Wireless Coachlink for Supplemental Braking Systems - Braking Indicator System, part # SM99945, with the Demco Air Force One Braking System. I have included a product description link and a video installation of this product below.
    view full answer...
  • Does the Demco SBS Wireless Coachlink Still Activate When the Vehicle is Being Driven Not Flat Towed
    I contacted the manufacturer regarding your questions about the Demco SBS Wireless Coachlink for Supplemental Braking Systems # SM99945. They were able to tell me that if you have the the transmitter wired to the vehicle’s stop switch, yes it will transmit anytime the brake switch is activated. When the transmitter is activated it uses milliamps, no power is taken when the transmitter is NOT activated by the switch.
    view full answer...
  • Will CoachLink 9000 Wireless Transmitter Indicator Set Work With Air Force One on 2018 Ford F-150?
    Yes, the SMI CoachLink 900 Wireless Transmitter and Receiver Braking Indicator Set # SM99945 will work with the SMI Air Force One Supplemental Braking System # SM99243 with your 2018 F-150. The transmitter uses a blinking LED and audio tone to alert you when the brakes in your F-150 are being applied. I have added a photo showing you how it will wire with the Air Force One, and according to the instructions, this is how it will install: - Connect the red wire on the Wireless CoachLink...
    view full answer...
    Image 1 for
  • Does Demco CoachLink Monitor Work w/ Air Force One Braking System That Didn't Come With it
    It sure will! You can absolutely add the CoachLink monitoring system to your Air Force One supplemental braking system even if it didn't come with it. The transmitter is just three wires that connect to the Air Force One's reed switch, and the receiver just plugs into your RV's 12 volt outlet and you're set. To add the CoachLink you will need the following: - Demco SBS CoachLink 900 Wireless TranDemco SBStter and Receiver Braking Indicator Set # SM99945 I have added links below to the...
    view full answer...
  • Wireless Braking Indicator for Demco SBS Stay In Play DUO Braking System
    Sounds like you are looking for the Demco SBS Wireless Coachlink for Supplemental Braking Systems # SM99945 which is the wireless braking indicator for the Demco SBS Stay-IN-Play DUO Supplemental Braking System # SM99251.
    view full answer...
  • Brake Light Indicator For Demco Stay-IN-Play Braking System Inside Motorhome
    You will want to use the Demco SBS Wireless Coachlink # SM99945 with the Demco SBS Stay-IN-Play DUO Supplemental Braking System # SM99251 to receive notifications inside your motorhome. The LED light that comes with the Stay-IN-Play is only for wiring inside the vehicle being flat towed. Since the Coachlink is wireless you will not have to do any wiring inside your motorhome.
    view full answer...
  • Indicator Light Recommendation for Use with Brake Buddy Classic Brake System
    The Brake Buddy system is a manufacturer we don't carry, but it sounds like you simply want to know when your vehicle brakes are being activated so I do have a solution for you. You can use the Roadmaster Universal Brake Monitor # RM-9530 which will be an easy LED system to give you the information you are seeking. I've attached a couple of videos to assist.
    view full answer...
  • Will the SMI CoachLink 900 # SM99945 Work With the SMI Air Force One # SM99243
    The SMI CoachLink 900 Wireless Transmitter and Receiver Braking Indicator Set, part # SM99945, will work well on your 2012 Honda CR-V with the SMI Air Force One Supplemental Braking System for Motor Homes with Air Brakes, part # SM99243, as long as there is a signal running through your stop light switch wire when you are towing your Honda. Since the CoachLink 900 works off of the signal that runs through your stop light switch, you will want to test to make sure there is signal when...
    view full answer...
  • How Does Demco Air Force One Reed Switch Install on Vehicle with Battery Disconnected
    Since your battery is getting disconnected via the Roadmaster Battery Disconnect # RM-766 what you'll need to do is wire the reed switch directly to the battery as the power source instead since the wiring of the vehicle is getting bypassed. This would be the same if you were to install the Demco SBS CoachLink 900 Wireless TranDemco SBStter and Receiver Braking Indicator Set # SM99945 as well.
    view full answer...
  • Supplemental Braking System Recommendation Uses Light Indicator for When Brakes are On and Error
    The Blue Ox Patriot part # BLU37TR would be more what you are looking for. The remote of this system that installs in the tow vehicle will show a display light when the brakes are applied and then has an additional light that illuminates when there would be a problem. The Patriot is our most recommended system to as it installs very easily and works very well. The SMI makes noise everytime the brakes are being applied.
    view full answer...
  • Is SBS Wireless Coachlink for Braking Systems Worth Installing
    The Demco SBS Wireless Coachlink for Supplemental Braking Systems # SM99945 does provide some peace of mind that your towed vehicle brakes are getting applied so that you know for sure that your braking system is working. Some braking systems have something like this so it's not something I would recommend for every towing setup but I would say it provides enough of a benefit to outweigh the cost.
    view full answer...
  • What is the Difference In The Demco Stay-IN-Play # SM99251 and # DM86VR?
    First we have the Demco SBS Stay-IN-Play DUO Supplemental Braking System # SM99251 which is the typical system most will see. We then have the Demco Stay-IN-Play DUO Supplemental Braking System w/ Wireless Coachlink Monitor # DM86VR. This 2nd kit includes the Demco SBS Wireless Coachlink # SM99945 which allows you to visibly see when the brakes in your flat towed vehicle are activated. This is much easier to see on the monitor inside your vehicle then trying to see the LED lights mounted...
    view full answer...
  • Comparing Demco Air Force One Supplemental Braking Systems For a 2022 Jeep Wrangler
    The Demco Air Force One Kit # DM26VR comes with Wireless Coachlink. The Wireless Coachlink # SM99945 tells you visually and audibly if desired, when the brakes on your towed vehicle are being activated. The Demco Air Force One Kit # SM99243 is the same system as above without the Wireless Coachlink. You would have to rely on the LED indicator lights that are mounted inside the Jeep to know when the system is braking. The Demco SBS Second Vehicle Kit # SM99209 only contains the parts...
    view full answer...
  • Can the Monitor Light and CoachLink be Hooked to the Same Wire
    For starters, a 2015 Jeep Grand Cherokee and 2015 Jeep Wrangler are very different vehicles in regards to flat-towing components so looking at installation videos on a Wrangler is just going to confuse you. The Grand Cherokee actually does not have an active stop light circuit so you will need to use the Roadmaster Stop Light Switch Kit part # RM-751449. The Jeep Wrangler does have an active stop light switch circuit which is why you need to use the Roadmaster Brake-Lite Relay Kit part...
    view full answer...
  • Installing an Indicator Light for Dinghy (Flat) Towing
    The long and short of it is that you need to route wiring from the cold side of the stop light switch (only gets hot when brake pedal is pressed) on your dinghy up to the location that you are mounting the RoadMaster Replacement LED Display Monitor # RM-300065-00 in your motorhome. The red wire is for power and the white wire is for ground. If you are able to add an extra wire from your towed vehicle and route it up to your motorhome then you are more than welcome to do so. Otherwise...
    view full answer...
  • Transmitter For Demco Air Force One And Stay-In-Play Duo Supplemental Breaking Systems
    Yes, the transmitter can be purchased with the Demco SBS CoachLink 900 Wireless TranDemco SBStter and Receiver Braking Indicator Set # SM99945 so that you can use both your Demco Air Force One Supplemental Braking System w/ Wireless Coachlink - Air Brakes - Proportional # DM26VR and Demco Stay-IN-Play DUO Supplemental Braking System w/ Wireless Coachlink Monitor - Proportional # DM86VR.
    view full answer...
  • How to Install Stay-IN-Play Indicator Light on Motorhome for Flat Towing
    There are a few different ways to get the indicator light from the Demco SBS Stay-IN-Play DUO Supplemental Braking System # SM99251 operating in your motorhome. If you don't plan on using the brake controller circuit on your motorhome then you can connect the indicator to your motorhome by using that circuit. Tap in a wire from the stop light circuit on your towed vehicle to the connector at the front of your towed, making sure it corresponds to the brake controller pin on your motorhome...
    view full answer...
  • Which is Preferred Connection for SMI CoachLink 900 Wireless Transmitter
    The SMI CoachLink 900 Wireless Transmitter and Receiver Braking Indicator Set # SM99945 that you mentioned comes with a couple butt end connectors and a couple quick splices for tapping into a circuit. I personally don't care for quick splices as the few times I've tried to use them I either ended up cutting the circuit I was trying to tap into or didn't press the blade hard enough to get the circuits to contact. The best connection would be to solder it. For that we have the part # FL0803490...
    view full answer...

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Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Jameson C
Expert Research:
Jameson C
Employee Joshua S
Video Edited:
Joshua S
Employee Jacob T
Video Edited:
Jacob T
Employee Kathleen M
Video Edited:
Kathleen M
Employee Randy B
Test Fit:
Randy B
Employee Shane H
Test Fit:
Shane H
Employee Clayton O
Test Fit:
Clayton O
Employee Chris R
Video by:
Chris R
Employee Michael B
Video by:
Michael B
Employee Wilson B
Updated by:
Wilson B
Employee Kristina F
Updated by:
Kristina F
Employee Amanda M
Written by:
Amanda M
Employee David F
Installed by:
David F

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