Originally Posted by preston805

My question is has anyone out there switched to one of the short roof-top antennas, ..... can I simply buy one of those, drill a hole in the roof and extend the antenna cable up to it and hook it up?

Originally Posted by preston805

Does the RF amplifier need a power source?

Originally Posted by MLEE4984

Sorry to bring ths thread back from the dead, my antenna is making clicking noises, it goes up and down fine at the moment. Would you guys say that it's the motor or the mast itself?

Thanks in advance,
-Mike

Originally Posted by MLEE4984

What type of lube would you use?

Originally Posted by gazi001

I found that this topic was well covered but fragmented. Also there were no complete instructions as to how to get to the motor.
So here goes...
You may need to completely replace the antenna motor on your RX300, or if you are lucky, only the long flexible nylon rack of the antenna itself is broken. Usually if the antenna will not retract fully, it means the antenna rack is damaged or broken. If the rack is broken off, the motor will need to come out to get at the broken part.
You will need a pair of needle-nosed pliers, a long-handled medium flat screwdriver, a small flat screwdriver, a Phillips crosshead screwdriver, a 10mm spanner and a 12mm spanner.
You may get away with replacing the antenna by unscrewing the chromium-plated nut that secures it on the outside. I used a pair of needle-node pliers to turn it, and once it was loose, a long-handle screwdriver on one side only was sufficient to turn it. It took a while as the thread on the nut is deep. Be patient. Once you have it off, you can pull the antenna straight up. If it's all there, just worn, simply replace it, using the antenna installation instructions at the end of this article. If it is broken off, read on…
Remove the external plastic trim piece that was held down by the antenna nut. Go inside the car, remove the rear deck carpet and the removable strut that contains the rollout luggage cover, and fold down the right-hand rear seat.
The key part you will need to move in order to get at the motor is the vertical carpeted wheel arch panel on the right side of the luggage compartment. Note, you will NOT need to remove any of the trim around the window. Remove the little door in this panel that normally conceals the first aid kit.
Go to the very front of the rear deck and pull up firmly on each the five popup fasteners that hold the front edge of the hinged deck that covers the spare wheel. Underneath you will find two 12mm bolts that hold the hinges. Remove these and the deck comes out. Remove the tool tray and covers.
Many of the fasteners you will have to remove are of the press-in-pop-out plastic type. The black ones have a slot in the top, into which a small screwdriver can be inserted horizontally. If you do this and then use another screwdriver as a levering point, these fasteners come out very easily.
Using this technique, pop up the fasteners that attach the plastic moulding that runs across the bottom of the doorway, and has the door latch coming through it. There are four black fasteners visible on the inside. Be sure not to lose these fasteners, as they tend to fly out and travel quite some distance. Underneath there are six more fixed fasteners hidden. Do not be afraid to pull firmly.
Similarly pry out the fasteners that hold the right-hand black storage bin. There is an additional screw-in one in the floor of the bin. Remove the bin.
Remove the two 10mm screws holding the black luggage tie-down rings at right front and right rear of the compartment.
Pry up and remove the plastic cover on the top of the right hand interior wheel arch.
Your next target is the L-shaped moulding at the lower right of the rear doorway. There are two black pop fasteners at the bottom, and a couple more hidden ones at the top.
You now have a good view of the carpeted moulding and its attachments, two fasteners in the vertical part at the rear, and one mounted horizontally at the front. Remove the two at the rear first, then go inside the right rear door and pry out the one at the front corner.
Carefully pull the fastener at the top inside corner of the large plastic moulding on the front of the wheel well, the one that has the seat belt tidy clip attached to it. This is the only action you need to take on this moulding, leave the rest of it untouched.
You now have enough fasteners removed to pull out the carpeted panel far enough for you to be able to reach the antenna motor easily. From the back edge, push down on the top and pull to the left at the same time. It should hinge from the front fairly easily without detaching completely. I used a short piece of 2x4 to wedge in there to hold the moulding open.
There are two 10mm nuts holding the antenna motor in place. Remove them and pull the motor out. As soon as you can reach it, detach the antenna cable from the radio (at the top of the motor) and pull out the drain pipe from the bottom of the wheel well, leaving the pipe attached to the motor.
Now all you have left is the electrical connection. On one side of the white plug is a tab, which you need to press in with a screwdriver or other suitable tool, and the plug should come out easily. If it doesn't come out easily you are not pressing hard enough on the tab.
Now you have the motor in your hands.
Unscrew and remove the support bracket, noting where the ground wire is attached..
Unscrew the screws holding on the casing of the motor, and CAREFULLY separate the two halves of the case, holding the main body underneath.
Inside this casing there is a small quantity of grease for lubricating the mechanism, so try not to get it spread everywhere.
Lift up the circular plastic rack storage can, and inspect its inside. You may find a broken piece of the toothed nylon antenna extension rack coiled up in there. This may be the root of your original antenna problem. Remove and discard it.
Take a look at the open mechanism. Notice the path from where the antenna emerges, down into the mechanism. On the underside of the white circular plate are the teeth that drive the rack. When installing the new antenna, you will need to insert it correctly relative to where these teeth are.
Replace the storage can, reinstall the motor cover and screws, and the support bracket, together with the ground wire.
Now it's time to put it all back together again.
Hold the motor close to where it installs, and in the correct orientation, but before you fix it in place, make sure you reattach the signal cable from the radio, and the power hookup, and reinsert the drain pipe through the hole in the wheel well.
Carefully slide the motor back to its correct location and loosely reattach the two 10mm nuts. Make sure the exit hole of the antenna is correctly located relative to the hole in the bodywork before you tighten the nuts.
Do not be tempted to replace all the panels just yet.
Here is where you rejoin if you do not need to get at the motor.
It helps if you have a friend or SO available to help. Ask him/her to turn the ignition key to the radio-only position, and turn on the radio. You should hear the motor start to operate. It will keep running for a while until it times out. Wait until it stops. The mechanism is now in "antenna up" mode.
Take your new antenna and fully uncoil the rack, making sure you remove all the twist ties it came with from the factory.
Fully extend the telescopic metal part of the antenna as far as it will go, drawing the rack into the metal tubing. With the rack teeth facing FORWARD, insert the end of the rack into the antenna hole where it emerges from the bodywork. You may need to wiggle it until most of the rack that is still showing goes in, at least six inches or more, at which point it will go no further. It should not require any force.
Holding the antenna directly vertical above the hole, ask your friend/SO to turn the radio OFF. The motor will start the mechanism to retract the antenna. If you have inserted it far enough, and it is facing in the right direction, the mechanism will take hold of the end of the rack and draw it entirely into a tight coil in the circular cup inside the motor. As it draws in, guide the metal part of the bottom of the antenna into the motor body in the correct way. The antenna should withdraw completely as it used to.
Reinstall the black plastic trim moulding from the outside, and screw the chromium-plated nut back fully down on the antenna.
Have your friend/SO turn the radio on and off several times, waiting each time for the mechanism to cycle completely. The antenna should fully extend when the radio is switched on, and fully retract when it is switched off.
If you were just replacing the antenna mast itself, you're done.
For the rest of you, it's time to tidy up.
Carefully push the carpeted side panel back into its correct position, replace the wheel arch top plate and pop in the single brown fastener on the front side of the wheel arch.
TIP: At this point, the order in which the rest of the parts go back is not obvious, so when you insert one of the black pop-up fasteners, only insert it very loosely, in case you need to remove it again to attach something else to the same hole.
Reinstall the plastic cover over the spare wheel, the side bin (with its nut at the bottom holding it down), the L-shaped piece at bottom right of the door opening, and the moulding across the bottom of the tailgate door opening, with the several hidden fasteners and the four black ones.
ONLY when you have everything back in place, should you go round and fully press in the black pop-up fasteners.
Reinstall the luggage tie-down loops with the 10mm bolts.
Reinstall the rear compartment deck by reattaching the hinges with the 12mm bolts, and pop back the fasteners on the hinged trim piece.
Put back the first aid kit door.
Finished.
Enjoy. (Courtesy of truebr1t of US Lexus Owners Club)