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Curt 7-Way to RV Socket LED Circuit Tester - Vehicle End

Curt 7-Way to RV Socket LED Circuit Tester - Vehicle End

Item # C73NR
Our Price: $19.05
Electrical Tools
Shipping Weight: 0.22 lbs
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This circuit tester plugs into the 7-way connector on your vehicle. LED lights indicate which functions (brake, turn, tail, stop, reverse, electric brakes, and 12V) are properly working. Color-coded LEDs make it easy to distinguish each signal. 1-800-940-8924 to order CURT electrical tools part number C73NR or order online at etrailer.com. Free expert support on all CURT products. Great prices and Fastest Shipping for Curt 7-Way to RV Socket LED Circuit Tester - Vehicle End. Electrical Tools reviews from real customers.
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  • Reviews (31)
  • Q & A (0)
  • Videos (2)
  • Photos

CURT Electrical Tools - C73NR

  • Testers
  • Circuit Tester
  • Tow Function Tester
  • CURT

This circuit tester plugs into the 7-way connector on your vehicle. LED lights indicate which functions (brake, turn, tail, stop, reverse, electric brakes, and 12V) are properly working. Color-coded LEDs make it easy to distinguish each signal.


Features:

  • 7-Way connector tester plugs into your vehicle's wiring harness to confirm your lights are functioning
    • Tests tail lights, brake lights, turn signals, reverse lights, electric brakes, and auxiliary power
  • Labeled LED lights indicate which functions are working properly
    • Color-coded LEDs make it easy to distinguish each vehicle signal
  • Integraded resistors are compatible with Smart Tow


58272 Curt 7-Way RV Blade Connector Tester

Installation Details C73NR Installation instructions



Video of Curt 7-Way to RV Socket LED Circuit Tester - Vehicle End

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for Review of CURT Electrical Tools - 7-Way LED Circuit Tester - C73NR

Hi there. I'm Michael with etrailer.com. Today we're gonna take a quick look at this Curt 7-Way to RV Socket LED Circuit Tester. Now this 7-way connector tester is going to plug into your vehicle's wiring harness to confirm your lights are functioning properly. You can see we do have a color-coded and labeled set of LEDs here that are going to make it very easy to distinguish your vehicle's signals. So, if we work from the bottom here, you can see we've got our TM for our tail lights.

We've got our LT for our left turn signal and our RT for our right turn signal. Those will both light up for our brakes, so we can check our brakes. We've got the BU for our backup, BK for our electric brakes, and then our 12V for our auxiliary power. So this will be very easy to operate. Just plug it right in, apply your turn signals, brakes, electric brakes, that sort of thing.

It will light up to indicate that it's functioning properly. We can loosen this screw on the backside that will allow us to twist that LED head so that we can get that lined up in whatever orientation is gonna be easiest for us to view as we are testing those out. So we'll just take a little bit of backing out of that screw there, and then we can twist the head to whichever orientation is gonna be easiest for us to see, and then tighten it back down so it always be able to make sure that we have a very easy time just to plug this in and then operate those signals, make sure that they're working properly. So that completes our look for today. Again, I'm Michael with etrailer.com.

Thanks for watching.


Customer Reviews

Curt 7-Way to RV Socket LED Circuit Tester - Vehicle End - C73NR

Average Customer Rating:  4.7 out of 5 stars   (31 Customer Reviews)

This circuit tester plugs into the 7-way connector on your vehicle. LED lights indicate which functions (brake, turn, tail, stop, reverse, electric brakes, and 12V) are properly working. Color-coded LEDs make it easy to distinguish each signal.

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This has been a reliable and useful product thus far. I use it every time before I tow. One time I had a blown fuse in the tow vehicle for the trailer lights and caught it before I made the trip to pick up my trailer at an offsite location.



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This tester is a must When troubleshooting trailer electrical problems. Just plug it into the 7 way socket and get the big picture of your harness output circuit condition. Quickly and easily verify the performance of your tow/running lights, brake tights and hazard lights. Must have tester for all Rv and trailer owners!



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Identified the electrical issue with the wiring.



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I had an electrical issue with my 5th wheel connector and needed to troubleshoot it. I immediately thought of etrailer and had the tool delivered to my campsite. Problem solved.



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It works, but I really haven't had a need for it.



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Arrived on time and in good condition. Seems to be good quality. Have not used it yet.



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After struggling with erratic trailer lights checking ground connection, light bulbs and possible shorts, I finally decided to check my truck connection. The curt 7-way tester revealed my trailer circuit breaker to the running lights was blown. Replaced it and problem solved. Took less than 5 minutes with the curt 7-way tester to reveal my problem. If I had already purchased this tester before checking out my trailer it would have saved me the 2 hours I spent diagnosing the trailer first. Outstanding product and a big thank you to etrailer for carrying this product. Plus the video provided by etrailer on their website does a great job explaining how to use the device.



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Swift and smooth experience



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Just what I needed to figure out why our lights weren't functioning properly! Worked perfectly.



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The product arrived on time. Work's like it should.



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works great



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Worked perfectly right out of the box.



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See what our Experts say about this CURT Electrical Tools

  • Troubleshooting No Power From 12v Circuit on 2015 Chevy Silverado 1500
    It sounds like you're not getting power on the 12v circuit on your 7 way connector and you've tested this either with a circuit tester like the # PTW2993 or a tester like the # C73NR. It's possible that the fuse for the 12v power on your 7 way connector on your 2015 Chevy Silverado 1500 has blown; I would check the fuse box in the engine compartment and look at fuse # 2 to make sure that it's in good working order. This could be the reason that you're not getting any interior lights turning...
    view full answer...
  • Flashing Trailer Lights with a 2008 Mercedes GL450 with Factory Tow Package
    It sounds as if you have the trailer ruled out as the problem. I would recommend you check the ground connection on the trailer, to make sure it is connected securely to clean metal, so you eliminate that as a potential problem. I would then look at the connector on the vehicle. Try using a tester, part # C73NR to check if all circuits are functioning. If you find a problem at the connector, since the tow package is factory, not aftermarket, I would recommend you check with your Mercedes dealer.
    view full answer...
  • Troubleshooting Left Turn Signal Staying Hot on a 2013 GMC 3500HD Towing a Trailer
    If you used a 7-way circuit tester like our 7 Way Trailer Connector Vehicle Tester # C73NR and the LT circuit stayed lit that would indicate that there is voltage on this circuit at all times which means something is shorting out onto this circuit. Due to the fact that it is hot all the time it would seem that it is the 12 volt power circuit that is shorting to the left turn/brake circuit. I suspect you have a 7-way round connector since on these style connector the left turn and 12 volt...
    view full answer...
  • 2006 Ford F350 With OEM Brake Controller Not Reading Trailer
    When using the wiring diagrams you speak of, it is important to remember that wire colors can vary, and it is best to wire by function rather than wire color. The easiest way to determine which wiring circuit preforms which function is to use a car battery, ground the white wire from the trailer connector lead to the negative battery terminal, and apply 12 volts to each of the remaining circuits in order to determine their function. By going this route, you can be sure that the connector...
    view full answer...
  • Why Does My Trailers Turn Signals Work But The Brake Lights Dont?
    If you aren't getting brake lights but you are getting turn signals, you have a bad ground somewhere. Brake and turn signals are run through the same circuit on a trailer and this will be the only viable reason for this to be happening. With that said, I recommend first checking the grounds up at the lights. These should be clean, have a solid connection, and not be stacked with other ground sources. Stacking grounds is a pretty common practice, but it is always better to have a ground...
    view full answer...
  • Recommended 7-Way Tester that is Compatible w/ Ram Factory Brake Controllers
    I haven't heard of the Curt 7-way tester not working with OEM brake controllers. There was a Tekonsha tester that had problems with Dodge and GM trucks so it is possible. We have been able to confirm that the Pollak 7-Way to RV Socket LED Circuit Tester item # PK12741 is compatible with Ram factory controllers. The Curt 7-Way to RV Socket LED Circuit Tester item # C73NR and item # C66NR are the same testers they're just a different color. There is one thing to note about the use of...
    view full answer...
  • Can a Breakaway Battery and Deep Cycle Battery be Charged off of the Same 12 Volt Line
    What you could do is use the center pin on a 7-Way and instead of having the reverse light circuit on that pin you could remove the wire that is there and run a 10 gauge wire, such as # 10-1-1 sold by the foot, from it up to the truck battery via a 40 amp circuit breaker # PK54540. Then run wire from the center pin on the trailer side to the deep cycle battery to maintain it. This way the batteries each have their own 12 volt source and there is no chance of back feeding. Another option...
    view full answer...
  • Brake Controller Causing 7-Way Trailer Connector to Flicker
    Like most other brake controllers do, the Draw-Tite Activator IV, part # 5504 sends a small test pulse of voltage through the brake output circuit to confirm that the trailer is plugged in and that the brake magnets are receiving the signal. This would explain the flickering you're getting on the # C73NR 7-way tester. Are the connectors on the vehicle and the trailer in good condition? If they're older, and you see any white or green corrosion on the pins or sockets, there's a chance that...
    view full answer...
  • No Interior Lights on a 2019 Legend Manufacturing 7X27 Inline Snowmobile Trailer
    The first thing I would check is that the bulbs did not blow out for some reason. This can be done by popping off the lens cover and inspecting the filament. The interior lights are generally ran to an auxiliary battery on the trailer or directly from the 12 volt power on the vehicle's 7-way. If they are ran to an auxiliary battery then make sure the battery has a sufficient charge. If they are not ran to an auxiliary battery then odds are they receive power from the vehicle's 7-way and...
    view full answer...
  • No Stop/Turn Signals on Trailer Lights for a 2008 Ford F-250
    For starters, I would check that the fuses responsible for the right and left hand stop/turn signal circuits are in working order. These are located in the fuse box, the right hand stop/turn signal fuse is a 10 amp in the #F36 slot and the left hand stop/turn fuse is also a 10 amp but in the #42 slot. If both the fuses check out then you would need to locate the left and right hand stop/turn signal wires at the back of the trailer connector and then trace these are far back as possible...
    view full answer...
  • Parts Needed to Install Always-On 12V Power Circuit on 2018 Ford Super Duty
    Ford did decide to change the operation of the 12V auxiliary power circuits on newer trucks. The fix for this annoying circumstance is easy enough. All you need to do is bypass the existing 12V circuit with a new direct battery connection that will allow the 7-way to have active 12V power at all times, regardless of the ignition key position or operation of the brake pedal. You will need just a few parts to accomplish this: circuit breaker # PK54540, 10-gauge wire # 10-1-1, ring terminals...
    view full answer...
  • What is AX Auxiliary Pin on Hopkins 7-Way Trailer Connector
    The AX (Auxiliary) location on the Hopkins 48505 connector that you reference, which is the same one used on the Hopkins # H20046, is typically used for 12V power. If you take a circuit tester like part # PTW2979 or # C73NR you should see that the corresponding pin on your 2012 GMC Sierra 7-Way (in the 1 o'clock position) has constant 12V of power running to it. What you would connect this to on your trailer are things like your batteries, a trailer jack, or anything that would need to...
    view full answer...
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  • Troubleshooting Trailer Wiring Where 12 Volt Accessory Circuit Isnt Active
    It's not uncommon for a 7-way trailer wiring connector to not have the 12 volt circuit active. Sometimes this is just due to a bad fuse or breaker which you can check under the hood of the vehicle. Other times you have to run a 10 gauge wire like # 10-1-1 from the positive post of the 7-way through a breaker like part # 9510.
    view full answer...
  • Solution for 12 Volt Power Accessory Circuit on 2017 Ford F-250
    The 12 volt power circuit of the 7-ways on the newer Ford trucks like your 2017 Ford F-250 is an odd situation. Many people have the same issue as you or they have found that the gauge wire used for this circuit is just too small to power anything. Best option is to bypass it all with 10 gauge wire like part # 10-1-1 and a circuit breaker like part # 9510 to run from the pin on the 7-way all the way to the positive pin of the truck battery. This will give you a circuit active whenever needed...
    view full answer...
  • Troubleshooting Brake Controller in Vehicle that Stops Working Intermittently
    You did an excellent job troubleshooting your brake controller issue so far. It sounds like there's a bit of corrosion on the pins of your 7-way which is preventing the controller from making a solid and consistent connection. Try taking some sandpaper to the pins of your 7-way (specifically the brake output 5:00) position and most likely will get you going. If you find that your 7-way is corroded or damaged to the point of needing a replacement an easy solution is the part # HM40975 which...
    view full answer...
  • No Power to the 12 Volt Pin on a 7-way Trailer Plug on a 2001 Ford F-250 7.3L Powerstroke
    I looked up your owner's manual online and the 12V power issue is likely a fuse issue. You will want to check the 30amp fuse number 16. This will be in the power distribution box under the hood.
    view full answer...
  • How To Determine Compatibility of the Autowbrake Electric Brake Controller
    The Autowbrake Electric Brake Controller part # 3430001 simply requires an active battery charge line circuit which is a wire run from the trailer connector to the battery to provide a small charge for the trailer battery while in tow. This wire should have been installed along with the 7-way. That said, you can test this using a test light or plug-in tester like the 7 Way Trailer Connector Vehicle Tester part # C73NR. If the circuit is not active you can activate this yourself using wire...
    view full answer...
  • My Camper Battery Does Not Hold A Charge
    I am assuming the battery is in working order. If your are not sure, I would check the battery. If you have a battery tester, I would charge the battery and leave it overnight and see if it has a charge in the morning. If it does not, I would start with replacing the battery. If the battery holds a charge, I would move on to checking the 7-Way trailer connector. If you are using a 7-Way trailer connector you want to check and see if the 12V pin is hot when the truck key is in the ignition....
    view full answer...
  • How to Get Constant Power to a Vehicles 7 Way Plug
    You can definitely run constant power to the 7 way if needed. All you would need is a length of wiring and a circuit breaker. Twenty feet of the Deka 12 Gauge Primary Wire # 12-1-1 would give you a bit of excess, but it never hurts to get a little more than ending up needing a little more. I highly suggest going with a 40 amp circuit breaker since this will be installed directly in line from the battery to the 7 way plug. You will need to remove the 12 volt power wire from the 7 way, which...
    view full answer...
  • 12 Volt and Reverse Light Circuits Not Working on 1999 Ford F-250 Tow Package
    There are also relays associated with the reverse light and 12 volt circuits for the tow package wiring on a 1999 Ford F-250. There are also multiple fuses for each. If any one of them is bad or missing then that circuit will not work. The relays are in locations 38 and 39 in the fuse panel so those are the first to check. There are also a fuses in locations 4 and 16 in the under hood panel and in location 28 in the in-cab fuse panel.
    view full answer...
  • How To Activate 12V Trailer Charge Circuit On 2019 Ford Super Duty With Factory 7-Way
    If you have already added the fuse and the trailer charge circuit is not activated in the 2019 Ford F-350 Super Duty with factory integrated brake controller, then you want to make sure the trailer is connected and you press the brake according to a Ford Service Bulletin on their factory integrated brake control with trailer module 12V charging system. There may also be a dash setting to activate the tow/haul mode on the 7-way before the 12V output is activated.
    view full answer...
  • Could Center Pin of Trailer Wiring 7-Way be 12 Volt Accessory Circuit
    You basically already did verify that the center post of your 7-way is the 12 volt accessory circuit. Normally the center post is the reverse light circuit and the 12 volt pin is the 1:00 pin position. If your center pin is hot all the time then it would be the 12 volt accy circuit.
    view full answer...
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  • Activating 12 Volt Accessory Circuit of 2002 Ford F-150
    Easiest way to activate the 12 volt accessory circuit of your 7-way will be to run a length of 10 gauge wire like part # 10-1-1 (sold by the foot) through a breaker like part # 9510 from the positive post of your battery to the 1:00 of your F-150's trailer wiring.
    view full answer...
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  • Troubleshooting 2019 Ford F-150 Having No Power To 7-way Connector After Replacing Fuse
    I would be happy to help. Since you replaced the Trailer Tow Parks Lamps Fuse 53 in your 2019 Ford F-150 and are now not getting any power to your 7-way connector, I recommend checking fuse 43 as it is for the trailer tow park lamps module. If that doesn't fix the issue go ahead and check fuse 103 and 74 as that is the two fuses for the other lighting functions. If you have still have no power to any of the pins of your 7-way connector, and none of the fuses in question are blown, I...
    view full answer...


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Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Joshua S
Video Edited:
Joshua S
Employee Chris R
Video by:
Chris R
Employee Rick G
Video by:
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Employee Wilson B
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Wilson B
Employee Michael B
Installed by:
Michael B
Employee John A
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Employee Sabrina W
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Sabrina W

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