Aftermarket Radio Antenna Issue

[runsgrateasanut]

When parts arrive from U.S. will be installing a Sony Xplod thats sat around on my shelf for two years.

Read a warning that if I have a power Antenna fixing blue wire can damage Antenna if no Relay in circuit. I've installed a few Radios in my time but not seen this warning before. Does the Lexus have a Relay for this Antenna. Any advice on subject? Assuming disconnecting Battery at neg. a wise precaution pre installation. Seen the very good help video on installation.

[ambermarine]

I don't think there is an electrical motorised unit on the lexus Ls400 that has not got some kind of relay ,thats why it as a virtually perfect electrical system and very few blown bulbs,I never had a bulb go in 190k miles on my 22 year old Mark 1.

The blue box on the antenna next to the connection plug as all the circuitry for the motor and antenna hieght control for frequency change etc,so I would imagine there is some kind of relay in there.

I am not sure as to weather there is a relay in the fuse boxes dedicated to the antenna.

The antenna always goes up and down a moment after the ignition is turned on or off which signals the operation of a relay.

Just a note to this;

The relay that is connected to the antenna array is not for the antenna it is the rear fog light Relay.The reason I know this is when my Mark 1 unit failed I replaced it with an aftermarket unit until an oem replacement came up on eBay.

I disconnected the wires to that relay thinking they were for the antenna I was taking out and three years later my car failed its MOT because the rear fog lights were not working ,enough said, don't use them anymore.

[runsgrateasanut]

Thanks - I forgot I had a copy of the Wiring diagram for a 1990 LS400 and sure enough it shows an Ant Relay on page 19. So assuming same for 1993 model, I should be safe.