Community Forums

Rick 2005 Dolphin 5376 · 04-01-2008, 05:45 PM

Thanks Sarge. You confirmed what I started to think. The cooltech harness is NOT plug and play and it's only a few that have noticed it. I left them a message this morning but did not get a call back. I'm going to run over to my local Fry's Electronics and spend $2.12 on a couple of Diodes and place them in the harness back by the tail lights. As a side experiment, I will unplug Fuse M37, (Brake and Stop Light Switch) and see what the results are as well. I sure didn't ask enough questions when I bought the cooltech harness and assumed that they had placed a couple of diodes in line. This will get fixed but I'd hate not to have the skills I have the resources we have here on IRV2 to fix it with out a trip to a service tech.

offthewall · 04-01-2008, 06:10 PM

Quote:

Originally posted by Rick 2005 Dolphin 5376:
Thanks Bill. You confirmed what I started to think. The cooltech harness is NOT plug and play and it's only a few that have noticed it. I left them a message this morning but did not get a call back. I'm going to run over to my local Fry's Electronics and spend $2.12 on a couple of Diodes and place them in the harness back by the tail lights. As a side experiment, I will unplug Fuse M37, (Brake and Stop Light Switch) and see what the results are as well. I sure didn't ask enough questions when I bought the cooltech harness and assumed that they had placed a couple of diodes in line. This will get fixed but I'd hate not to have the skills I have the resources we have here on IRV2 to fix it with out a trip to a service tech.

Rick,

I don't think the diodes are going to help. What you need to do is stop the Jeep from applying the brake lights itself. What you want is only the signals from the Motorhome to activate the lights. The simplest way is to defeat the Jeep's brake light switch. Roadmaster makes a commercial version of the "homemade" relay I fabricated. In fact if you configure their Evenbrake system on the website for a Jeep Wrangler, they require their relay as part of the installation. So it's not the cooltech harness or your particular setup but a fact of life with an aux braking system on an 07-08 Wrangler while using the Jeep's lights rather than separate bulbs.

CoolTech · 04-01-2008, 09:44 PM

Rick,

This is Kendall at Cool Tech. offthewall is right, please don't add any diodes as this will not solve the behavior you re experiencing. There is a much easier solution.

Here is what is happening: As we all know, on the Jeep, there is only one lamp (filament) that is used for both STOP and TURN. When stopping, the Jeep provides a continuous 12v signal to this lamp and when the turn signal is activated, there is a pulsing 12v signal to this lamp. When we add the Cool Tech LLC harness, there is still only one lamp (filament) and both the Jeep and the MH want to control it. When your MH turn signal is on, it is properly applying a pulsing 12v signal and the light responds. (So far, so good.) When the MH starts to brake with the turn signal still activated, the MH properly applies a pulsing 12v signal. (Still good.) However, inside of the Jeep, the brake assist that you have begins to depress the brake pedal - activating the Jeep's brake switch. The Jeep then applies a CONSTANT 12v. signal since the Jeep has no clue that a MH turn signal is on. Back at the light, the bulb (filament) is "seeing" a constant 12v source so it no longer is pulsing - it just stays on constant.

A diode solution will not fix this. A fancy relay system would - but a far easier solution is to disable the Jeep from messin' with the lights while towing. This can be easily achieved by removing the "M1" fuse as shown in the picture below. The IOD fuse should also be lifted for towing (see my previous post in this thread for the current draw with/without this fuse.)

I thank-you very much for bringing this problem to my attention. All persons using a brake devices should follow this simple procedure. I will update the Cool Tech instructions to incorporate this advice.

Rick 2005 Dolphin 5376 · 04-02-2008, 05:22 AM

Thanks. No diodes. From looking at the owners manual I thought I would pull M37 but if you say M1, M1 it is. What a great forum. I can't thank the people here enough for all the work we do to keep our lifestyle in RV land.

offthewall · 04-02-2008, 05:27 AM

Quote:

Originally posted by nota4re:
Rick,

This is Kendall at Cool Tech. offthewall is right, please don't add any diodes as this will not solve the behavior you re experiencing. There is a much easier solution.

Kendall,

I wish I had thought of the fuse solution. My mind always goes to the "fancy" way to solve a problem. In fact, I had completely designed the Roadmaster relay product from scratch before I knew of it's existence

CoolTech · 04-02-2008, 05:31 AM

Quote:

From looking at the owners manual I thought I would pull M37

You and me both! That was my first try - but the brake lights still work! So, I had to get the Service Manual outand look at the schematics, finally concluding that it is the M1 fuse. My neighbors already think I'm weird, I'm sure. I'm out under the hood of the Jeep at almost midnight flashing pictures so I could show the fuse location on the forum !

I agree that this is a great forum for MH owners!!

Rick 2005 Dolphin 5376 · 04-02-2008, 05:39 AM

I'll give it a go this weekend. We full time it for now and the DW isn't thrilled about moving the MH out everytime I come up with a new project or test.
Thanks guys. Everything went to perfect last week when I spent the day under the car installing painting and wiring. I'm glad it was just a silly fuse.

SargeW · 04-02-2008, 08:25 AM

What about this solution... instead of pulling another fuse every time, what if you spliced a toggle swithch in the line at the brake switch under the dash?? Would that stop the Jeep from sending the signal to the brake lights??

Rick 2005 Dolphin 5376 · 04-02-2008, 08:41 AM

Can you reach up there to do that? I'm thinking pulling the fuse is not to much work. We are already in the box pulling the big white one anyway. I can't get to the Jeep right now. Are you going to look under there?

offthewall · 04-02-2008, 11:18 AM

Quote:

Originally posted by SargeW:
What about this solution... instead of pulling another fuse every time, what if you spliced a toggle swithch in the line at the brake switch under the dash?? Would that stop the Jeep from sending the signal to the brake lights??

That was the solution I already used before going the relay route -- it does work. The relay has the advantage of being automatic. Either solution, relay or switch, the worst that can happen, if you should forget to turn it back on (or the relay fails) is that only the center brake light on the Jeep is out. The normal Left/Right brake lights still work. I haven't gotten my head around that one yet other than the fact that the center brake light is directly connected to the brake light switch and the tail/brake lights are controlled by the CANN computer buss. Don't know what the M1 fuse pulled does, have no need to try that now that I have the relay installed.

Flints AR Mike and Lorrie · 04-02-2008, 03:00 PM

I tow a 07 Warngler and wired the tail lights using a diode block and wired it into the correct wires on the rt side kick panel-note the running lights use 2 separate wires!

Rick 2005 Dolphin 5376 · 04-03-2008, 06:11 AM

I don't think anyone is confused, other than maybe buying a product with inaccurate installation instructions. Had Sarge and me not done a few experiments, it most likely would of gone unnoticed. Thanks to Cooltech for updating their side of it and thanks to the rest of us for putting up with me during the period of severe frustration in not knowing why I was having a problem with something that no one else was having. I take towing very seriously and am now happy with my install and very happy that someone just getting started on this journey will have less trouble with their install. Bill, it would be great if you updated your very early posts on this topic so new folks won't have to read 24 pages before they get to this part. Thanks again to everyone.

Rick 2005 Dolphin 5376 · 04-03-2008, 10:55 AM

I'm not going to go on about this but I will close by saying that something like the cooltech harness should of addressed the need to pull M1 under certain conditions. My situation is no different than any one elses. The Jeep is applying the brakes and the brake light switch on the jeep is interfering with the whole connection with the RV if the RV doesn't have seperated turn and brake lights. I beat my self silly and a few people here did the same, trying to figure it out. Now that Cooltech is updating their instruction booklet, it will be plug and play for those who come after us. As far as updating your earlier post. Why not? A simple addition to the end of what is well regarding as a fine DIY is all it takes. I'm not thinking that making people read 25 pages to get to the end of the story is serving anyone. I know I spent way to much time figuring it out and if you ask my DW, she'll give ya her version.
In my other business, Aerospace contract manufacturing, crossing t's and dotting i's is where's it at. How many posts flew around here because of a simple omission that, wouldn't of affected everyone, certainly affected me and a few other cooltech customers.
Thanks Bill, for being the keeper of this thread

FourEyes45 · 04-03-2008, 12:42 PM

Today we got the Cool Tech harness,Blue Ox base plate and the Aventa LX tow bar installed on our 08 4door Rubicon,last week we installed the SuperHitch with a 36"ext. on our TV.Just had to try it out for a few miles today.

Thanks to all of Post on this site--It help.
I know Iknow Overkill on the Hitch and tow bar but will not have to worry.
Have a safe and great day.
Walter