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In Japan the FM radio has a smaller frequency range, therefore the radio does not receive FM stations transmitting above XXMhz. This means that a radio expander needs to be fitted, this shifts the frequency range that the radio can receive.
After the radio expander is installed the radio will display a different frequency to that which is being received. i.e. If you tune into a station at 104Mhz and have an a 10Mhz expander installed the radio will display 94Mhz. Another side effect of installing a radio expander is that if two radio stations are are transmitting at a frequency differential the same as the frequency shift of the expander the radio will pick up both stations at the same time. ie station A transmits at 84Mhz and station B transmits at 96Mhz and you install an expander with a 12Mhz shift, when you tune into station B you will pick up both stations at the same time.
The radio in the Toyota Soarer has a dual aerial which means 2 expanders should be fitted for best reception. A lot of places only install one expander because it is cheaper and easier. Following is the instructions on how to install dual expanders in a Soarer with an EMV(tv screen). If you have a car without the EMV screen then the expander needs to be fitted to the back of the radio, this is not covered here.
1. The radio is located on the passenger side under the back seat, the picture below shows where the original aerial plugs into the radio.
<add picture of radio location showing aerial plugs.>
2. Unplug the two aerial plugs, notice that one of the plugs is smaller than the other, this causes a problem in that (to my knowledge) an expander with the smaller plug is not available. To get around this problem cut the smaller plug off, and cut the plug off one of the expanders. Then resold the small plug onto the expander and the plug from the expander onto the wire from the aerial where you cut the small plug from. See below.
< Picture showing expanders with small plug changed. >
3. The aerial wires can now be plugged into the expanders and the aerial plug on the expander can be plugged into the radio. Put the bigger plug in first as the hole for this is the lower of the two. The expander also requires power and should be connected to an accessories power source. This is shown in the picture below.
<Picture showing the power connection for the expander >
4. Check the radio now by tuning to a radio station above XXMhz. If it works you can put the back seat back in and all is done.