ISO is an international standard connector used by all radios that is equipped with every new radio network (female ISO). When installing the radio, they must be connected (with ISO) (push-fit).
Some cars have an ISO connector for radio wiring harness, allowing you to install the radio in minutes. If you do not have a standard ISO connection, this is not a problem. All you have to do is make a cable connector (unique to the car model) to fit your car's standard radio wiring harness to the new radio ISO.
If the male connector in the car fits into the radio, they simply click on it. An exception to this rule is that some cars, most notably Vauxhall and VW, require minor modifications to the configuration of the power input.
If the ISO connectors were connected, the radio would be ok, but if the ignition switches off and the buttons are removed, the radio loses memory settings (stored radio stations may be lost and the inserted CDs will be subtracted). This is because power lines (yellow: permanent live and red: ignition live) are connected to bad roads, these car models.
Many radio modems are now equipped with wired harness adapters that use bullet connectors with cable glands. Simply disconnect the bullets, turn on the yellow and red wires, and then re-connect them.
Or in older cars when the radio is switched on (can be switched on without the ignition key). In such cases, the yellow and red wires must be connected to the radio cable. It is possible for the manufacturer's radio wiring to be used (with the use of ball-point connectors in the line wiring harness) to be fitted with the wiring harness of the car's wiring harness. This means that when the two ISO joints are pressed, the power supply is moved to the appropriate cable positions
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