Trailer Brake Controller Connector (2 Viewers)

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Joined the club with a redarc brake controller. Took the easy route and also got the harness meant for Toyota. Had met Marc back at expo east 2019, definitely a good dude and helpful. Had messaged him before ordering to make sure I had the right stuff.
One thing that shocked me was it took a good 25mins to recognize direction of travel with first trailer hookup. Thanks @Brucey

View attachment 2407464
Great to know. I have the controller installed but have yet to tow anything. Soon I hope.
 
Having trouble with my Redarc Controller. Here is the problem. Then I will describe how I did the install. (FYI, I am in contact with Redarc about this but no fix yet.)

First, the controller appeared to have installed fine. I even used it for a couple of short trips and it worked great. Then ...

I plugged in our travel trailer to the trailer plug on the LC as I usually do. I then checked all of my lights (turn signals, brakes, etc.) to make sure everything worked which they did. Then I got in the LC and noticed that the light on the Redarc control dial was blinking - green, green, blue. Sort of like a dash, dash, dot. And as I was driving the trailer brakes were not being activated. So I pulled off the highway and tried to diagnose the problem. I downloaded the user manual PDF and found a chart that points out particular issues based on the "codes" which are different colors flashing in certain sequences. I disconnected the trailer, let the car sit, etc. but kept getting the same "error code" (if that is what it is). Since we were only about 10 miles from home we cancelled our trip.

I had the LC in for service so I asked them to clean the socket. The next step was to use a trailer plug circuit detector to see if we were getting current to all of the wires. Plug it in to the "socket" under the bumper of the LC and everything looked good. But the problem didn't go away. Didn't make a difference. I then put dielectric grease on the connections. Still no difference. So I pulled everything out and used a butt connector on the blue wire as I had been told that is the one that controls the braking. Did not fix the problem. Finally, I disconnected the black wire from the LC battery. Voila! The "fault" went away and we headed off on our next trip. It took a while for the controller to auto-adjust but it worked. Arrived at our destination, camped for a couple of days, hooked up the trailer to leave and as soon as I plugged the trailer into the socket on the LC the problem was back. Sigh. Not having time to diagnose it I disconnected the LC battery again (black wire) which reset everything. Then the problem went away and we were able to hook up and get home. But that didn't last. Headed over there yesterday to check things out and the problem is back.

Redarc support told me to test and see if the voltage on the blue wire varies from 4-12 when the brakes are applied but I have neither the tools or the knowledge of how to do that.

As background, here is how I did the original install.
  • I had previously been using a Tekonsha P3 with no issues.
  • I snipped the wires from the Tekonsha P3 controller "plug" (blue, white, red, black).
  • Then I "spliced" them to the Redarc harness matching the colors and using wire nuts wrapped in electricians tape.
  • I used industrial strength, double sided velcro tape to secure the main unit to the left side of the silver "box" under the dash. (See attached pic)
  • I secured all of the wiring with zip ties to ensure they would not be bouncing around.
  • Then I installed the control dial and closed everything back up.
As I indicated earlier, all of this worked great for the first couple of trips. The only change was that I had to replace the control dial as I had originally ordered the wrong switch panel blank.

Also, when I took apart the blue wire and reconnected it with a butt connector I also flipped the main unit so that the colored wires are easier to get to and the cable that runs to the dial is on the far side of the unit. (If that makes sense). I did this simply in case I needed to get in there and fix the splices on the other wires. (Since I secured the main unit with velcro I was able to slide a pot scraper between the velcro layers to remove the unit and then reinstall it.)

Bottom line - has anyone seen this issue? Anything beyond "guesses" as to what may be happening?

Thanks,
Dan

IMG_2639.jpeg
 
This sounds eerily similar to what I had going on with my set up (Tekenosha P3) and my camper. The problem could be a combination of your trailer pig tail/7 way plug and the harness in back. I ended up taking some emery paper (could even use some sand paper), pulling the cover back from the pig tail and disconnected a terminal one at a time (started with the black wire) and sanded off all the corrosion on each terminal. As I put it back, I added some dielectric grease to each terminal as I tightened it down. I honestly couldn't tell that there was any corrosion, but was worth the try. I also found a small file that I could fit down inside each pin and filed away at each one for a bit. I then moved over to the wiring harness at the back of the LC and tried my best to file down each of the prongs at least a bit. Then put some dielectric grease in each pin of the pig tail and plugged it back into the LC and then pulled it back out a few times. Haven't had any trouble since. I'm now going to add it to my yearly camper maintenance plan. Hopefully it helps!
 
@Dan Higgins, if you have a multimeter, you can test the voltage. Set it to Volts and put the red lead on the blue wire and the black lead onto the white wire (or really any metal which is part of the chassis ground), then press the brake.

1600273235897.png


Aside from that all I have are educated guesses.

If the lights were a steady green-blue-green-blue flash that means it's calibrating. But if you're actually seeing green-green-blue repeated then I suspect it's 2 different error codes (unless Redarc has additional error codes they don't print in the manual). See below from the manual:

1600272724487.png


You could have a bad wiring harness (maybe one of the wires is cracked inside the plastic sleeve and you can't see it, or one of the pins to connect it to the factory harness is loose?) or one of those wires might not be as tight in the wire nut as you think it is. It could be a bad controller but the sequence above and the fact that it happens at start up makes me think it's wiring.

One other thing it could be is a problem with your 7 pin harness on your trailer. It seems unlikely but I have had one time when my trailer lights worked but the brake controller didn't come on... pressing in the harness and adjusting it slightly made it connect. In my case the contacts in my trailer harness are mucked up and it wasn't making contact (I need to replace this at some point). But I suppose maybe if you have a short in the trailer wiring harness or a loose connection at the junction under your trailer frame perhaps that could trigger it

If you were close to me I'd offer to swap brake controllers with you for a bit to see if the problem goes away for you and/or starts for me.
 
Thanks, Geoff! I was hoping I could avoid the multi-meter thing as doing that level of work makes me nervous simply because I have never done it before. But your instructions make it sound very simple! Also, I am becoming quite proficient at removing the dash and having rotated the controller it is easier for me to access the wires. Time to go buy a multimeter!

I am really hoping that it is not underneath the trailer but I will check that. Not sure the plug/socket are the issue. I do use an extension since I have a ProPride hitch which creates a bit more distance between the trailer and the LC and given where the LC socket is located it doesn't easily reach. But I purchased a new extension with heavier gauge wiring (per Mark Bruce at Redarc) and it didn't make a difference.

Thanks for posting that chart. That is what I have been working from and my belief is that the problem is one of the first two conditions. I have been focusing on the blue wire. Maybe I need to re-splice the red wire. I'm thinking of redoing them all using those new heat-shrink sleeves that have the solder built in. But, again, this is totally new territory for me and I don't want to make things worse.

A question. In that chart, it says to disconnect the Black wire and reconnect it again after 1 minute. Do they mean the black wire to the controller? I guess they are assuming that I can easily access the controller? Plus, that doesn't seem like it would fix the problem - just reset the unit. This is essentially what I was doing by disconnecting the LC battery's black wire. But the problem didn't go away.

Also, I sent a video of the light sequence to Mark Bruce at Redarc to see if I am interpreting the "codes" correctly. But he is on holiday until tomorrow (his time) so I don't expect to hear back from him until at least tomorrow morning.
 
You can't do effective electrical work without using a multimeter. You need one for diagnostic testing, or else you are just guessing.

Wire nuts are not automotive grade splices. After testing the brake signal as directed by Redarc, the very first thing I would do is replace those splices with a soldered heat shrunk connection, or worst case, butt splices.
 
Thanks, Geoff! I was hoping I could avoid the multi-meter thing as doing that level of work makes me nervous simply because I have never done it before. But your instructions make it sound very simple! Also, I am becoming quite proficient at removing the dash and having rotated the controller it is easier for me to access the wires. Time to go buy a multimeter!

I am really hoping that it is not underneath the trailer but I will check that. Not sure the plug/socket are the issue. I do use an extension since I have a ProPride hitch which creates a bit more distance between the trailer and the LC and given where the LC socket is located it doesn't easily reach. But I purchased a new extension with heavier gauge wiring (per Mark Bruce at Redarc) and it didn't make a difference.

Thanks for posting that chart. That is what I have been working from and my belief is that the problem is one of the first two conditions. I have been focusing on the blue wire. Maybe I need to re-splice the red wire. I'm thinking of redoing them all using those new heat-shrink sleeves that have the solder built in. But, again, this is totally new territory for me and I don't want to make things worse.

A question. In that chart, it says to disconnect the Black wire and reconnect it again after 1 minute. Do they mean the black wire to the controller? I guess they are assuming that I can easily access the controller? Plus, that doesn't seem like it would fix the problem - just reset the unit. This is essentially what I was doing by disconnecting the LC battery's black wire. But the problem didn't go away.

Also, I sent a video of the light sequence to Mark Bruce at Redarc to see if I am interpreting the "codes" correctly. But he is on holiday until tomorrow (his time) so I don't expect to hear back from him until at least tomorrow morning.
I used heat-shrink butt-splice connectors on mine. Solder would be better but it's not required if you get a good crimp. The heat shrink just protects the crimp from corrosion and also reduces the strain on the wire

Voltage is easy to measure and nothing to be scared of. You can put the leads directly on your battery to confirm it's 12V, for instance. If you put them on backwards it'll just read -12V.

The Redarc manual is referring to the black (hot) wire going into the brake controller, not the negative battery cable. I'd have to look at the Toyota wiring diagram but I would assume that wire doesn't have power when the vehicle is off, so I don't know why you'd need to disconnect the battery itself from the whole vehicle. But if I'm wrong and the TBC is always drawing a tiny voltage to retain the memory then you could simulate removing the black wire by just disconnecting the harness from the controller for a few seconds then plugging it back in. You're correct though - it won't fix the issue, it just "reboots" the controller.

(I suspect the flashing lights are because something is loose and simply turning the vehicle completely off and back on would "fix" the issue in the same manner, unless the TBC has a small parasitic draw when the vehicle is off... in which case unplugging the TBC at the harness for a few seconds should accomplish the same thing as pulling the negative battery cable, but with less effort)
 
Having trouble with my Redarc Controller. Here is the problem. Then I will describe how I did the install. (FYI, I am in contact with Redarc about this but no fix yet.)

First, the controller appeared to have installed fine. I even used it for a couple of short trips and it worked great. Then ...

...
  • I snipped the wires from the Tekonsha P3 controller "plug" (blue, white, red, black)....

Cheap option that might help is purchasing the harness from Redarc that is meant for Toyota. Since you spliced wires maybe that is where your problem lies? The harness from RedArc is around $20. Plugs into the TowPro and has a connector on the other end to plug into the Toyota harness.

Also when you get that "error code" is it only on the one specific trailer? If you plug up to another trailer after seeing it does it still persist?
 
Geoff, if you are interested I did test the circuits as you suggested. Black probe in the White and red probe in the Blue. Pressed the brakes. Nothing. Now looking at the Redarc chart above I also tested the Red wire. When I pressed the brakes the Red wire immediately went to 12v and from there on up to 25v. That tells me that the Blue is not getting anything. That is the splice I connected using a butt connector. Maybe I didn't get that right?
 
Sorry. I wrote my previous post before the replies from @linuxgod and @afgman786. Thanks for that input and walking me through the learning process.

Geoff, it is interesting that the error code or blinking lights begin as soon as I plug the trailer cable into the 7-pin socket on the LC. The engine is not running and it is not in Accessory mode.

@afgman786 if I purchase Redarc's cable for the 2016 LC what would I connect it to? What I have done is use the existing wires from my previous Tekonsha and matched the colors after snipping off the connecter that plugs into the Tekonsha controller. As I am thinking this through that means that I am splicing in to the wires from the Tekonsha harness. What would that harness be connecting to?
 
Having trouble with my Redarc Controller. Here is the problem. Then I will describe how I did the install. (FYI, I am in contact with Redarc about this but no fix yet.)

First, the controller appeared to have installed fine. I even used it for a couple of short trips and it worked great. Then ...

I plugged in our travel trailer to the trailer plug on the LC as I usually do. I then checked all of my lights (turn signals, brakes, etc.) to make sure everything worked which they did. Then I got in the LC and noticed that the light on the Redarc control dial was blinking - green, green, blue. Sort of like a dash, dash, dot. And as I was driving the trailer brakes were not being activated. So I pulled off the highway and tried to diagnose the problem. I downloaded the user manual PDF and found a chart that points out particular issues based on the "codes" which are different colors flashing in certain sequences. I disconnected the trailer, let the car sit, etc. but kept getting the same "error code" (if that is what it is). Since we were only about 10 miles from home we cancelled our trip.

I had the LC in for service so I asked them to clean the socket. The next step was to use a trailer plug circuit detector to see if we were getting current to all of the wires. Plug it in to the "socket" under the bumper of the LC and everything looked good. But the problem didn't go away. Didn't make a difference. I then put dielectric grease on the connections. Still no difference. So I pulled everything out and used a butt connector on the blue wire as I had been told that is the one that controls the braking. Did not fix the problem. Finally, I disconnected the black wire from the LC battery. Voila! The "fault" went away and we headed off on our next trip. It took a while for the controller to auto-adjust but it worked. Arrived at our destination, camped for a couple of days, hooked up the trailer to leave and as soon as I plugged the trailer into the socket on the LC the problem was back. Sigh. Not having time to diagnose it I disconnected the LC battery again (black wire) which reset everything. Then the problem went away and we were able to hook up and get home. But that didn't last. Headed over there yesterday to check things out and the problem is back.

Redarc support told me to test and see if the voltage on the blue wire varies from 4-12 when the brakes are applied but I have neither the tools or the knowledge of how to do that.

As background, here is how I did the original install.
  • I had previously been using a Tekonsha P3 with no issues.
  • I snipped the wires from the Tekonsha P3 controller "plug" (blue, white, red, black).
  • Then I "spliced" them to the Redarc harness matching the colors and using wire nuts wrapped in electricians tape.
  • I used industrial strength, double sided velcro tape to secure the main unit to the left side of the silver "box" under the dash. (See attached pic)
  • I secured all of the wiring with zip ties to ensure they would not be bouncing around.
  • Then I installed the control dial and closed everything back up.
As I indicated earlier, all of this worked great for the first couple of trips. The only change was that I had to replace the control dial as I had originally ordered the wrong switch panel blank.

Also, when I took apart the blue wire and reconnected it with a butt connector I also flipped the main unit so that the colored wires are easier to get to and the cable that runs to the dial is on the far side of the unit. (If that makes sense). I did this simply in case I needed to get in there and fix the splices on the other wires. (Since I secured the main unit with velcro I was able to slide a pot scraper between the velcro layers to remove the unit and then reinstall it.)

Bottom line - has anyone seen this issue? Anything beyond "guesses" as to what may be happening?

Thanks,
Dan

View attachment 2437346

Are you sure it's not just recalibrating? I drained my battery during the installation of my NaviPlus unit and when I left for my latest camping trip, the unit recalibrated for about 30-45 minutes. Section 2.4 of the owners manual: https://cdn.shopify.com/s/files/1/2...2_Instruction_Manual.pdf?17391587134749800399
 
Sorry. I wrote my previous post before the replies from @linuxgod and @afgman786. Thanks for that input and walking me through the learning process.

Geoff, it is interesting that the error code or blinking lights begin as soon as I plug the trailer cable into the 7-pin socket on the LC. The engine is not running and it is not in Accessory mode.

@afgman786 if I purchase Redarc's cable for the 2016 LC what would I connect it to? What I have done is use the existing wires from my previous Tekonsha and matched the colors after snipping off the connecter that plugs into the Tekonsha controller. As I am thinking this through that means that I am splicing in to the wires from the Tekonsha harness. What would that harness be connecting to?

So when you had the Tekonsha hooked up originally, did you have that wired into your Toyota harness or did it have a white connector you plugged into the Toyota harness?

Here is a picture of what I'm talking about. The part circled in red would plug into the back of TowPro and the part circled in blue would plug into the Toyota harness. For me I had a white connector that I was able to just plug the part circled in red into. I didn't want to splice into any wires or anything, because like you mentioned wiring scares me.
1600293686948.png
 
Are you sure it's not just recalibrating? I drained my battery during the installation of my NaviPlus unit and when I left for my latest camping trip, the unit recalibrated for about 30-45 minutes. Section 2.4 of the owners manual: https://cdn.shopify.com/s/files/1/2...2_Instruction_Manual.pdf?17391587134749800399

Not recalibrating. It does do that after I reset it (by disconnecting the battery) and I know what that looks like. (Alternating green and blue where the blues get longer as it improves the calibration). It would be nice if it was that simple. In fact, when this first happened I was hoping that was it. But 10 miles and 20 stops into the trip is wasn't calibrating nor was it applying any brake.
 
So when you had the Tekonsha hooked up originally, did you have that wired into your Toyota harness or did it have a white connector you plugged into the Toyota harness?

Here is a picture of what I'm talking about. The part circled in red would plug into the back of TowPro and the part circled in blue would plug into the Toyota harness. For me I had a white connector that I was able to just plug the part circled in red into. I didn't want to splice into any wires or anything, because like you mentioned wiring scares me.
View attachment 2437750

Great question. The answer is YES! Though it took snipping some zip ties and disentangling a lot of cable to determine that what I had spliced into was in fact the Tekonsha harness plugged into a spot on the side wall of the Land Cruiser. I assume that I can simply get the harness you list above and replace all of the wiring I have done with that harness. Plug and play? Now the question is, how to source one of those harnesses before our camping trip on Sunday.
 
Great question. The answer is YES! Though it took snipping some zip ties and disentangling a lot of cable to determine that what I had spliced into was in fact the Tekonsha harness plugged into a spot on the side wall of the Land Cruiser. I assume that I can simply get the harness you list above and replace all of the wiring I have done with that harness. Plug and play? Now the question is, how to source one of those harnesses before our camping trip on Sunday.

Yup, exactly. Replaces the whole thing and is from RedArc. I purchased mine straight from their website and got it pretty quickly.
This is the harness I'm using. According to Marc it works on all 200s
RedArc Toyota Harness
 
Just spoke with Redarc support. Learned the following:
  • Yes, the controller continually pulls a tiny charge from the battery as it is in "standby" mode. Even when the vehicle is not running. The activates the Blue wire.
  • When you connect a trailer to the Land Cruiser the Blue wire senses that and wakes up the controller. During this start up is when my "problem" is being detected. (I pointed out that the green flashing lights happen as soon as I plug the trailer into the LC even though the LC is not "on" or in accessory mode or anything. The LC has been sitting, engine off, while I finish up the hitching process (WD bars, chains, etc.) the I plug it in. Straightaway the Redarc starts doing its green blinkies. I can look in through the driver side window and see it. The car is still off with no doors opened.
  • The other anomaly is that when I tested the red wire it went from 0 to 25+ volts when I applied the brakes. It did not stop at 12 as it should have on a 12v system. So something is definitely wrong with the Red wire circuit.
  • The tech support guy did say that the way I spliced into the Tekonsha harness will work if I did the splicing right. At the moment, I am suspicious of something else happening on that Red wire. Like maybe some feedback coming from the trailer or whatever. So probably no need to overnight a new harness. I probably could not get it in time anyway.
I may eventually replace my mess with the proper harness but I first want to make sure I don't have something else strange going on with the trailer or the trailer connection.
 
When I use at multi-tool should I set it to 12v or more? (see attachment picture). I am getting very high readings when testing a couple of wires. At first I thought it was an indication of a problem and that the problem was with the battery disconnect switch with the trailer. But then I realized that I was getting a strange reading on the multi-meter when testing out red wire on the brake controller at home - the trailer was not connected. My understand is that when I test the Red Wire using the multi-meter I insert the black multi-tool probe in the Black Wire slot and then insert the red probe in the slot I am testing for voltage. In this case I put it in the Red Wire slot and pressed on the brakes. The voltage on that red wire is supposed to go from 0 to 12. It went well past 12 on up to the mid-20s and beyond. At first I thought it was an indication of a problem. But now I am thinking that I was using the multi-tool wrong.

IMG_3249.jpeg
 
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@Dan Higgins you want it 180* from where it is. The spot circled in red will give you the accurate reading you need.
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Thanks, @afgman786. I'll re do all the testing tomorrow AM. I have a suspicion that I may be getting voltage from my trailer that is throwing things off and causing the Redarc to go into the green blinkys mode. Our new trailer has solar directly connected to the battery and therefore we are supposed to leave the battery connect switch (controls whether the trailer battery is connected to the tow vehicle) in the disconnected position. The battery is maintained and charged all the time by the solar panels. I noticed this afternoon that I had the switch in the wrong position. We'll see tomorrow now that I know how to use my fancy multi-meter. Definitely a learning process.
 

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