The 2003 Volkswagen Jetta Car Stereo features an eight-speaker audio system with an in-dash “double-DIN” combination CD player and tape player. Thanks to the double-DIN size mounting provisions for the radio, installers have a broader range of choice when selecting a suitable aftermarket unit. Although the removal and installation process for the audio head unit can be achieved in a relatively short amount of time, several accessories are required to adapt an aftermarket unit to the vehicle.
Open the vehicle’s hood and locate the battery. Disconnect the black negative battery cable from the “-” battery post, using an appropriate-size socket and ratchet.
Insert the four removal keys into each corresponding slot on the radio face, positioned at each corner, with the straight edges of each key pointed away from the radio.
Grasp the left side keys and pull on the radio while using outward pressure to disengage the locks. Perform the same action with the right side keys, until the radio is pulled out far enough to finish the removal process with your hands. Depress the raised portions of the locking mechanisms, located on the side of the radio’s chassis, to remove the keys.
Examine the rear of the radio and disconnect the antenna cable. Certain vehicles may include a second “diversity” antenna connection, which requires a dual antenna adapter. Take note that you must depress the connection tab on each antenna cable.
Disengage the locking lever on the square-shaped wiring harness block, located opposite the antenna connections.
Gather the wiring diagrams supplied with the aftermarket radio and wiring harness adapter. Remove the pre-cut insulated ends of each of the wires; twist the wires to prevent frays.
Crimp each wire from the harness adapter to the corresponding wires for the aftermarket radio harness, using the bullet connectors and with aid of the diagrams supplied with each product. Take note that the wire color-coding may not necessarily match between the products.
Wrap an overlapping layer of electrical tape over the splices to form a single group of wires. This will help prevent damage to the connections when installing the radio.
Connect the antenna adapter to the factory antenna cable(s), according to the product’s instructions. Do not connect the wiring harness adapter or antenna adapter to the radio at this time.
Mounting Kit installation
Fit the mounting kit to the aftermarket radio, using the product’s specific instructions. For DIN-size aftermarket units, slide the universal mounting sleeve off the radio chassis; install the mounting sleeve within the kit’s mounting hole. Use a flat-head screwdriver to bend the small sleeve tabs against the rear side of the mounting kit; this will secure the sleeve to the mounting kit.
Connect the radio wiring harness to the rear of the radio, followed by the antenna adapter.
Slide the mounted radio into the console opening. Do not slide in or fit the radio into the opening completely at this point.
Reconnect the negative battery cable to the battery. Test the new radio for proper functionality. If there appears to be an issue, turn off the radio immediately and check the harness connections.
Press the radio into place after making the necessary functionality tests. Testing the radio before finalizing the mounting process will avoid unnecessary complications with removing the car radio.