Sorry if this question has been asked before.

I recently got a 2004 LS430, and had my local dealer install the XM radio package. It included VAISTECH package and an XM mini antenna.

My LS has tinted windows.

The dealer installed the mini antenna on the dash, passenger side near the bottom corner of the windshield.

The reception on the XM radio is terrible. Passing any set of trees or buildings will cause a drop in signal.

Has anyone found a solution to this issue? I would like to mount the mini antenna outside, but the dealer said it will corrode and fail quickly. Ideally, it would great to incorporate the antenna in the shark tale navigation antenna.

Has anyone done either of these options?

 

The diagrams I'm looking at show the navigation system antenna under the top of the 2004 LS430 dashboard. Beginning in 2004, the rear roof antenna was used only for Lexus Link. From 2001 through 2003, the roof antenna was used for the dealer installed telephone unless the car had factory installed Lexus Link in which case the dealer installed telephone used a dealer installed imprinted antenna stuck to the rear window.

Many Lexus dealers installed the sat radio antenna on the trunk lid. Some forum members have hidden the sat radio antenna inside the high mounted stop light. Others have simply velcro'ed the sat radio antenna to the rear package shelf.

Do others in your area have good XM radio reception? Some areas don't. I've had sat radio only in rental cars and the reception has generally been spotty outside cities where there are few or no land based repeaters.

 

navigation antenna has nothing to do with xm antenna. xm antenna has to be more "exposed / direct" for good reception. i have installed vaistech xm kit on ls430 before, and the antenne was put directly on the rear deck (passenger side) and my friend says it's working well. the antenna wire is very long and no problem doing that.

of course, that depends on your tint. if you have metallic tint then it's going to block more signals.

in that case, putting it outside the car is the answer. i really don't know what the dealership is talking about on corrosion?! at least personally i haven't seen any and a lot of cars have the antenna mounted on the rear trunk lid. bad cosmetically, but functionally it works well

 

the center of the trunk front lip is where they intalled mine,, never a problem in open areas as ecpected,,

in very heavy tree coverage and under long overpasses you will lose the signal regardless of where it is mounted,,

Derry

 

same here,,

center of trunk lid back (closest to rear window). mine has been there for over 4 years and only recently shows any signs of wear from car washes it has a few small scratches. still works good.

 

Window Tint is lossy. I'm an antenna Engineer and if you have a tinted window and the antenna is inside, the 2.3 gHz frequency signal from xM radio is reduced by the tint. I've measured window tint at work when placed between antennas. Medium dark tint is in the 25 to 35 ohms per square resistant. Air is 377 ohms per square and your xM radio through loss is in the 5 to 8 dB range, plus one other very big item. With lossy/reflective material right atop your antenna, the antenna patterns on wide beamwidth antennas gets very unpredictably bad. Antenna on the top of the car is best. The signal to noise level for xM is 40 dB, take off 8 dB for tint, another 10 dB for bad antenna patterns, and it makes sense it's not so good.
The wavelength is 5 inches, (11.803"/frequency in gHz, which is pretty short, anywhere on the roof will work for the antenna.

 

This wont help you much, but have an aftermarket XM radio unit (Actually just quit on me) and my antenna is ran from the unit, under the steering wheel, up the pillar, and out the sunroof and centered on the front of the roof. Hardly ever worry about reception.

 

I installed mine behind the antenna on the rear of the roof.(pics attached) Only signal loss is when going through tunnels or concrete enclosed garages. I had a 1995 LS 400 previously and mounted my antenna on the forward portion of the trunk lid(hated the look but didn't take the time to change it.).
1. Start with the mount point behind the antenna.
2. Lift the rubber and thread the antenna wire to the left (or right side if you prefer) side of the car.
3. Lay it in the channel all the way to the front. Keep it taunt and it will not move.
4. Thread down between the windshield and rubber to the bottom of the windshield.
5. It's easier if you pull the bottom rubber piece out and put the antenna wire through it and back towards the door.
6. Pull the rubber at the top of the open door(looking toward the front) out part way and grab the wire to put it through the weather striping to the inside.
7. Thread the end of the antenna to where your XM is mounted.

You may be able to go through the firewall but I was lazy and went the door route since the exposed wire didn't bother me. If you are worried about water you can seal the various points with your preferred sealant but I've not seen an issue in five years.

 

Mine is inside the car on the back deck in the middle. No problems