Community Forums

ereadingrv · 06-15-2017, 02:37 AM

We have a Roadmaster InvisiBrake with a 2004 Jeeep Grand Cherokee Laredo. We're experiencing a strange issue, and we're hoping someone can point us in the right direction before we head into an expensive shop situation.

First, all rear lights are working fine on the Jeep when it's NOT hooked up. Brake lights, running lights, etc.

However, once it's hooked up, however, the left rear light assembly (at night) doesn't light up when driving.

Our understanding is that the InvisiBrake hooks up to a "central" area that controls all the lights as needed. Assuming that our understanding is correct (and it may not be), why would only the left light be affected? And only when driving with the lights on?

Thanks in advance for any help!

Skip426 · 06-15-2017, 08:09 AM

Quote:

Originally Posted by ereadingrv

First, all rear lights are working fine on the Jeep when it's NOT hooked up. Brake lights, running lights, etc.
However, once it's hooked up, however, the left rear light assembly (at night) doesn't light up when driving.
Thanks in advance for any help!

I have to ask .
Is this a problem with, only the the left rear park (running ) light on the Jeep , or do none of the left rear lights function ? Brake light ? Signal light ?

ereadingrv · 06-15-2017, 09:58 AM

Quote:

Originally Posted by Skip426

I have to ask .
Is this a problem with, only the the left rear park (running ) light on the Jeep , or do none of the left rear lights function ? Brake light ? Signal light ?

It is ONLY the park/running light WHEN HOOKED UP to the InvisiBrake. We haven't tested the turn signal, but brake lights on both sides of the Jeep work fine when it's hooked up.

Off of the hookup, all lights on the Jeep operate normally.

Skip426 · 06-15-2017, 10:47 AM

I should have asked in my first post .

Do you have the installation instructions from the Invisibrake ?
Somehow I'm having trouble wrapping my head around the Invisibrake being wired to the park lights.
Was the tow bar and related wiring done at the same time; as the Invisibrake ?
Did you do the wiring install , or was it done at a dealer or independent shop?
How long ago was the install completed?

Dark Sky · 06-15-2017, 03:51 PM

Another question, was the 'diode' approach used, or were dedicated towing bulbs incorporated into your taillight fixtures?
I assume all of the RV lights work correctly while towing, so the exact issue is that the left hand taillight does not light up when towing, but does light up when not towing.
This makes me think that you have had dedicated towing bulbs added, and you have a burnt out filament on the tow bulb on that side.

Please post what you find when it's resolved.

ereadingrv · 06-15-2017, 06:16 PM

Quote:

Originally Posted by Skip426

I should have asked in my first post .

Do you have the installation instructions from the Invisibrake ?
Somehow I'm having trouble wrapping my head around the Invisibrake being wired to the park lights.
Was the tow bar and related wiring done at the same time; as the Invisibrake ?
Did you do the wiring install , or was it done at a dealer or independent shop?
How long ago was the install completed?

1. Yes, we have the installation instructions.
2. Yes, the tow bar install (Roadmaster All-Terrain) was done at the same time as the InvisiBrake.
3. Independent shop. No longer in business, sadly. Gee, I wonder why...
4. August 2016.

ereadingrv · 06-15-2017, 06:20 PM

[QUOTE=Dark Sky;3650336]Another question, was the 'diode' approach used, or were dedicated towing bulbs incorporated into your taillight fixtures?

* No, these light assembly is a standard 2004 Jeep Grand Cherokee setup. Nothing has been modified for towing, outside the installation of the InvisiBrake and the tow bar on the coach/Jeep. Although we did recently replace the light assembly...see below.

I assume all of the RV lights work correctly while towing, so the exact issue is that the left hand taillight does not light up when towing, but does light up when not towing.
This makes me think that you have had dedicated towing bulbs added, and you have a burnt out filament on the tow bulb on that side.

*We actually just replaced the entire light assembly on that side with a brand new one from Jeep. The factory ones were prone to burn-out in the base of the light bulb seating.

Please post what you find when it's resolved.

Skip426 · 06-15-2017, 06:24 PM

As Dark Sky , has posted , read through the install instructions for words about " Diodes " or additional bulbs . You can check for additional bulbs , by seeing if the light bulb in the RIGHT rear lamp assembly is in the exact same spot , when powered from the Jeep's internal systems , as when powered from the coach.

YC1 · 06-16-2017, 05:42 AM

I have an Invisibrake and tossed the Diodes. I am using separate bulbs. Just way too many issues and dangers. However please read the following.

IF, it is ONLY the running light that is not working you may have dropped a wire when you replaced the light assembly.

I just reviewed the schematic and there is no need for diodes in the "running light" circuit. It should be one wire that feeds both sides.

If your wiring runs down the right side for example, there may be a wire that crosses over to the left that got missed. It is a very simple circuit.

Do you remember connecting any other wires up when you replaced the assembly? That is, did you just plug and play?

Pop the right assembly out and see if there is a stray wire and I believe it is brown that is used to power the running bulbs. Check your schematic to be sure of the color.

ereadingrv · 06-21-2017, 12:57 PM

Okay, the problem was remarkably easy to solve. We compared the wiring on the right and left sides, and discovered that one wire on the left side appeared to be fully-seated, but was not. Once we seated it properly, everything went back to working properly.

Thank you to everyone for all the suggestions, and to adding to the overall knowledge of the various possible causes of a problem like this!

Skip426 · 06-21-2017, 04:32 PM

Thanks for wrapping up your post ; glad it was an easy fix .
Question though .

Was the wiring problem in the toad , or in the connections to the coach ?

ereadingrv · 06-21-2017, 05:03 PM

Quote:

Originally Posted by Skip426

Thanks for wrapping up your post ; glad it was an easy fix .
Question though .

Was the wiring problem in the toad , or in the connections to the coach ?

The issue was the wiring in the Jeep, at the light. The InvisiBrake wire appeared to be properly seated; it even felt seated. But it wasn't. Once we figured that out, we seated it properly, and presto: lights on both sides of the Jeep.

Hope that clarifies things.

meddiver · 06-21-2017, 05:19 PM

Good to hear that you solved it. We had a similar problem and it turned out to be a dirty connection. The invisibrake connection(s) need to be kept as clean as possible. I keep a can of electrical cleaner and spray it almost every time we connect.
Safe and Happy Travels!

ereadingrv · 06-25-2017, 01:27 AM

Quote:

Originally Posted by meddiver

Good to hear that you solved it. We had a similar problem and it turned out to be a dirty connection. The invisibrake connection(s) need to be kept as clean as possible. I keep a can of electrical cleaner and spray it almost every time we connect.
Safe and Happy Travels!

That is a great tip! We'll be picking up some electrical cleaner soon and using it regularly!