How to Wire a GPS System in Your Vehicle
- 1). Attach the electrodes to the input and output components using a multi-meter to check the voltage of the existing system. Most positioning systems run on 5 volts. Step down 12-volt sources using a DC converter before wiring in the new GPS. The cigarette lighter also has a step-down function which you can use to power a GPS if re-wired.
- 2). Remove the old radio or compact disc unit from the dashboard using a screw driver that fits the screws in your vehicle. Often, you will need a flathead screw driver. Put aside the old unit.
- 3). Extract wires F5, F16 and F14 from the 16-pin plug in the vehicle. They are blue, gray and brown, respectively. Insert them into the 24-pin plug that comes with the new GPS system. Splice F5 and connect it to D1 (blue and yellow). Splice F16 and connect it to D11 (gray). Splice F14 and connect it to D20 (brown), as described by OEM Value.
- 4). Wire the new GPS to a DC, constant power source from the battery, to provide the new GPS with continual power. Power must flow to the GPS for the system to be effective, even when you have switched off the engine and have taken out the ignition key.
- 5). Connect the new GPS to an R12 plug to install an optional speed/reverse sensor wire. To do this, you will need to create your own R12 plug, which is not present in the vehicle to begin with. Extract two taped wires from a 4-pin CD-ROM to audio card connector cable. Connect the wire on the far left to the reverse switch. Connect the wire on the right to the speed sensor (speedometer). According to OEM Value, which specifically works with Toyota Camry vehicles, this can be the most difficult part of the installation.
- 6). Install a 5-amp fuse to protect the new GPS. Check that the new wires are securely fastened to their respective devices and are free from tugging and crushing. Hide the wires without stretching them too much. Plug the GPS antenna cable into the car's CPU. Fit the fascia of the new GPS using a screw driver. Test the system.
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