Hi all, my first post on your forums but have used them many times for answers to various problems. Thanks to all who have posted previously. When installing the Nikkai A66HY stereo into my 2006 vauxhall Zafira (06) I encountered a couple of things which I feel may be useful to others. The answers are available in bits and pieces throughout the internet using various other vehicle models and different versions of this unit. Ok here goes... Firstly, Remove the fuse for the car CD entertainment system. This is explained in the owners manual. Now remove the old radio and casing. If you have a CDR500 or equivalent the instructions to remove this are on the net in plenty of places. (You will need a torque screwdriver to remove the zafira's metal casing unit once you have the old unit out). Now pull the car's ISO connector through and make sure you have enough clearance behind to fit your Nikkai. At this point you should check that the radio powers on and is working fully. You will need an SD card, a USB stick, as well as a CD. Refer to the installation manual regarding CD retaining screws. Do not insert a CD if the retaining screws have not been removed. Connect the car's ISO plug to the ISO connector that comes with the radio unit and also connect the aerial. Now replace the main fuse in the fusebox. Insert the key and turn the ingition to number 1 and test that your radio powers on and you can receive radio channels. Insert your SD Card (Behind the faceplate) and play a song. Now test the USB function and CD. If you are happy that the radio powers on and all is working you can continue with the installation. If the radio does not power on check the fuse at the back of the unit, and also the main fuse. If you are fitting this to a vauxhall I suspect the standard ISO should be all you need. At this point you should check to see if your radio can store a radio channel. See below for instructions on how to do this. My problem was that the radio unit would default to factory settings each time i removed the ignition key. Now install the Nikkai metal casing unit in the single DIN slot. When you are satisfied that the casing is aligned correctly, bend the triangular metal pins outwards a little to hold the casing securely. There are four of these housed in the metal casing. Here's the tricky bit.... If you radio does not store radio channels or defaults to track 1 on your SD card when your key is removed you may need to do the following: - Swap the red and yellow pins in the ISO connector that comes with the Stereo Unit (Not the pins in your car's ISO Plug). To do this you simply use a small flat screwdriver (and with the male pins pointed towards you) press upwards against the pin you want to remove whilst pressing the pin through the other side. You won't get it to go all the way out but you will release the clip that holds the pin in place. Then give a small pull on the wire from the back and it should come out. REMEMBER which slot you removed the pin from. Do this for both the red and yellow wires and push the pins back through taking care to get them the correct way around. If you do not do this your radio will not hold any stations and each time you switch your radio on, it will revert to factory settings. Please bare in mind that the colouring of the wires may differ from my ISO unit. If you are in any doubt DO NOT DO THIS YOURSELF. Now you will need to connect the aerial adaptor (available through Maplins) to the car and the radio unit. Now connect the ISO units together and replace the main fuse. Before fitting the radio completely ensure the following: - 1. With the faceplate removed, the red LED on the main unit flashes without the key in the igntion. 2. Now attach the faceplate. 3. Insert key into ignition and turn to number 1. 4. The stereo should power on. If it does not automatically turn on press the power button on the faceplate. The unit should light up and default to 87.5 MHz. 5. Now remove the ignition key and the unit should power off. 6. Replace the ignition key and turn to number 1. The unit should power on and return to 87.5 MHz. 7. Now find a radio station that has RDS using the scan function or by pressing the two arrows (>>) to search. 8. When a station is tuned in and the RDS info is displayed, press and hold button 1 down until the radio beeps. A number 1 should now appear on the screen alongside the RDS info. 8. Turn the unit off and remove the key from the ignition. 9. Remove the faceplate 10. Replace the faceplate and turn the ignition back to number 1. 11. Press the power button on and your radio station/RDS info should be displayed with the preset 1 showing also. If you have an SD Card or USB stick with some tracks on, insert this into the unit. The radio will default to track 1 on the device and begin playing. Skip to a later track and let it play for 15 seconds. remember where you are up to. Now remove the faceplate then replace it. The radio should continue where it left off. You should also try this by turning the ignition off and back on. If your channels have not stored or the song does not continue where from the correct point you may need to go back to the beginning and make sure your connections are correct. Otherwise you should now have you radio connected correctly and you can finalise your installation. N.B. You will not be able to adjust the volume using your sterring wheel paddles. Im pretty sure this unit does not have the OEM facilty. If anyone manages to find a way of doing this please post here. Also if anyone has any other info about thei unit feel free to add to my post. Hopefully this should now be working fully.