Toad Tail Lights Installed

He said…

When last I blogged I had just finished installing the baseplate on our toad (towed vehicle)… The next day, I took another step to get the car ready to be towed; I modified the electrical system to the rear lights. Basically, anything you tow needs to have lights that function as the brake lights/turn signals – and this is what I was attempting to do.

Car without the lights installed.
Car without the lights installed.

This was confusing to start because the instructions that came with the kit didn’t really explain anything to a novice (of which I’m an expert at being).  It was also confusing because there were two different systems provided to me and I wasn’t aware of that either.  I thought all the parts had to be used.

YouTube is good.  If you can’t follow the instructions – watch a video of someone else doing the job.  That’ll clue you in… I eventually figured out that there were a couple different ways to set up the lights on the tow car to work.

One method is to drill a hole in each of the tail light housings and insert an additional bulb in each housing. These would be connected to the RV’s system via the tow harness.  Any braking or turn signal use in the RV would automatically light up these additional lights at the rear of the car.

The other method is to tap in to the existing wiring going to the tail lights that are already installed in the car.  This uses diodes that prevent “cross contamination” of the electrical signals when the car is attached to the RV. I chose to go with this system because I felt drilling into the housing and adding additional light bulbs would be more difficult.

I was wrong. More on that later.

The first thing that I had to do was route wires from the front of the car where the tow harness will be installed to the rear of the car.  This is a major pain in the *&^&* if you don’t have your car on a lift.  Suffice it to say I got dirty and squished.

Not a fun place to be.

Eventually, I was able to get the wires routed from front to rear.  This took me about an hour and a half.

After that, I had to remove the tail light housings so that I could get behind them to the car’s wiring and to pull up the wires that I just fought with.

Removed the tail light housing.

And then the scary part starts…  actually cutting into the wiring of the car.  This was nerve racking because there is VERY LITTLE slack in the wires.  There is no wiggle room for making a mistake (of which I’m a proud expert at accomplishing).

Not enough wire slack to play with.

I did it though… I cut into them wires and installed the diodes (the little black boxes in the picture below).

Diode’s installed.

Before I tightened everything, I attached the lights and made sure everything worked. Amazingly enough, they did!

Attaching the tail lights back to the car became my next hurdle.  I had to install two diodes and extra wiring between each tail light and the auto body.  Unfortunately, there isn’t that much room!  And it seemed that I was squishing something.  But I prevailed.

Until, that is, I tested the lights again.  All but one of the lights was working. Argh!  I pulled off the tail light and found a wire had pulled loose. Bummer. Tightened it again. Tested it. Reinstalled the tail light. Tested it. Failed again!

Double Arghh!

Pulled the tail light. Tightened it again. Tested it. Reinstalled the tail light. Tested it. Failed again!

Triple Arghhh!

Okay… so that whole thing about no slack… It’s haunting me now.  I finally decided to add in another foot of wire.  This gave me enough slack that the system is finally working….  for now.

The tow harness on the car.

I think the car is ready to be towed.  Once we get the tow bar, we’ll hook it up to my folks truck and pull car around to see how it fares!  Maybe there’ll be a blog about that in the future.

So, would I do this again?  Yes. But instead of using method #2, I’d go with method #1 and drill the hole in the taillight housing to add the extra bulbs.