i am aware that this is a common problem that people have suffered, and i am not just repeating an old thread. the problem is that other threads havent resovled this. i have done my research however i seem incapable of wiring my cd player in a way that causes the unit to maintain memory
the car is a 1990 ford fiesta
the unit is a sony cdx-gt210 xplod drive-s mp3 wma
if i wire the ground (black to brown), live (red to red) and constant (yellow to yellow) the unit powers up but it doesnt have any memory, i have also tried other combinations of this, sometimes it powers up, sometimes it doesnt but it never retains memory!
this is really frustrating me and any help offered would be much appreciated!
im not using a multimeter, im a bit of a a n00b and i dont have access to these things,
i have tryed many combinations of wiring though.
any other advice,
could it be that there is a problem with the car or the unit?
More likely the unit or the car wiring - since I'm assuming the car still starts and runs properly - colors on the car may have little or nothing to do with colors for the headunit in question. Try running a length of wire from the + post on the battery to the yellow wire on the headunit. If it remembers settings then it's a wiring problem, if it still forgets then it's a unit problem.
You need a multimeter because the car wiring is not as you expected. You should set the meter to check voltage. To make sure you are measuring correctly, first touch one lead to ground and one lead to positive on the battery to make sure you get a reading of 12 volts or thereabouts.
Then, you need to connect on lead of the multimeter to what you think is ground (the black wire) and what you think is constant on (yellow) with the keys out of the ignition. If you get 12 volts, you know that is right. If you don't, right away you have identified your problem. Keeping one lead connected to the ground, check other wires until you get a reading of 12 volts. Then connect that to your constant.
You aren't done yet. Now, keeping lead connected to your ground wire, put the keys in the ignition and turn it to the accessory 'on' position. (Usually one click below the point where the engine starts). Probe around for a wire that gets you a reading of 12 volts. Then, turn the car off and take the keys out. Check that wire again and see if you get 0 volts as a reading. If you do, that's your accessory wire. Connect it to red.
You're done. Not only do you have your stereo connected properly and can decide if it is defective or not, you now know how to use a multimeter to measure voltage.
NEVER, NEVER, NEVER believe that matching wire colors will work the way you expect- you are gambling and will surely be disappointed. Check and measure once, twice, three times with the meter. Otherwise, pay someone to install it for you. Imagine if you had accidentally connected your wiring backwards because you went by color. It would most likely have shorted and destroyed your head unit. You would be out the money for the HU, and also not sure if you might make the same mistake again.
its your twelve volt(constant)
the only wire that stays constantly on.
make sure u check were the other end of the wire finishes,
it mite of become detached from the battery
if everything is perfect there its something wrong with the head unit