|Here is the Liberty before the work started. The installation of the towing stuff started with the removal of the grill and the fascia.||The grill comes out pretty easy but the fascia is another story. There are three clips that hold the plastic fenders to the fascia and they are a BEAR to release.|
|The fascia finally comes off in one piece but it didn't give up easily.||Once the fascia is off, the rest is pretty easy.|
|Here you can see the covers on the front of the frame rail that get removed to install the nuts for the baseplate bolts.||Since the towing ears are removable, after it is back together, the only thing you can see is the brackets for the safety chains.|
|Here is a close-up of the baseplate after installation. Here you can see the socket for the towing ears.||The wiring was next. Here is one of the dual diodes for the stop lamps. See the text below for a full description of the hookup.|
|The left side uses higher current diodes since it is driving the trailer tail lights as well.||Here are the two diodes used to isolate the license plate light.|
|The harness under the hood coils up nicely in front of the fuse box. Notice the in-line fuses for the system. 10 amp fuses protect the wiring.||Final view of the Draw-Tite trailer hitch. It is rated to tow 5000 pounds! The 4 wire trailer connector tucks up under the panel when not in use.|
|In use, the wires go across under the hood and down into the space behind the grill. This works very well and is very easy to set up each time we tow.||Here's a shot of the wires coming through the grill. There are two harnesses. The larger of the two is for the lamps on the Liberty and the smaller is for remote control of the Brake Buddy.|
The wiring for the trailer hitch was taken care of by a light kit I ordered from E-trailer along with the hitch. It was simply a plug-and-play deal that converts the Liberty's red stop and amber turn to a 4 wire system for the four conductor trailer connector. It has connectors that go between the original tail light connectors and the harness. This drives a little box that determines how to energize the 4 wire harness for the trailer. It works well and was a lot easier than doing the wiring myself.
The wiring for the connection to the motorhome turned out to be a bit of a chore. I thought I could simply drive one of the front parking light wires and that would get the tail lights working. That was not to be. The Jeep uses SEPARATE circuits for the right and the left sides so when I tried to power the lights, it blew a 10 amp fuse in the left side circuit. The right side still worked fine but the left was dead. Back to the drawing board. Blue Ox suggests adding a separate bulb to the tail lamp housing but that seemed pretty cheesy to me. In addition, that would have allowed water and dust to get into the housings. After some thought, I decided to diode isolate the original lamps in the rear. Remember that since I had installed a hitch and a wiring harness, I wanted the motorhome to be able to drive not only the lights on the back of the Liberty but also the lights on a trailer in case we were pulling both the Liberty and a trailer.
I ran a three conductor cable along the left frame rail and into the left tail lamp area. Then I used a diode pair, (Motorola MBR2045CT) to isolate the stop lamps. The cathode goes to the lamp and one anode goes to the original wire from the Jeep and the other goes to the YELLOW wire in the three wire cable from the front. Now with 12V applied to the yellow wire, the left stop lamp lights but does not feed back to the Jeep. Another of these same devices was used on the right stop lamp and the second anode of this one is connected to the GREEN wire from the three wire cable.
The tail lamps turned out to be a bit more interesting. The tail lamps of the added trailer harness are all driven off the left side tail lamps of the Jeep so I needed a heavier diode to isolate them. I used a 6 amp bridge and connected to the AC in for the two anodes and the + out became the line to the original left tail lamp. Since this line drives the adapter mentioned earlier, this diode now supplies the power for the trailer tail lamps as well. The other anode in the bridge is connected to the BROWN wire in the three wire cable. The right tail lamp was isolated with a pair of 1N4001. 1 amp, 50 volt diodes. One of these diodes is connected to the BROWN wire as well.
The lamp for the license plate was isolated with a pair of 1N4001's as well and is connected to the BROWN wire in the three wire cable as well. The three wire cable goes into the engine compartment and terminates next to the battery. It is connected to the wire from the motorhome connector through three 10 amp fuses for protection. The green wire (Right Stop) from the three wire cable connects to the red wire in the motorhome cable. The yellow wire (Left Stop) from the three wire cable connects to the white wire in the motorhome cable. The brown wire (Tail Lamps) from the three wire cable connects to the black wire in the motorhome cable. The motorhome cable is 4 wires and the ground (GREEN) wire is connected to a screw near the fuses.
With this hookup, the motorhome uses the red stop lamps on the Liberty for both stop and turn, just as the motorhome does. The amber turn signals on the Liberty are not used by the motorhome wiring at all.
Incidentally, in doing this, I learned the wiring for the sockets of the tail lamps. If you look into the connector on the tail lamp, you will see two rows of contacts, one with two and one with three pins. If you orient the two pins on the left and the three on the right, the connections are as follows. The top of the two is the STOP lamp. The bottom of the two is the TAIL lamp. The top of the three is the amber TURN lamp. The middle of the three is the GROUND and the bottom of the three is the BACK UP lamp.
E-mail me at ultrasport(REMOVE)@mail.com
© Copyright 2002, 2003, 2004 Steve Das