I have a car stereo model pioneer KEH-1550 (cassete), and I don't know how to install. Can anybody tell me how to install it? Thank you.

You are not going to be able to find a new radio that will run a changer.

here is the manual to download, it explains how to set the clock

http://www.retrevo.com/support/Pioneer-DEH-P3600-Car-Receivers-manual/id/23231ci873/t/2/

Depends on the type of car you have. Do you have a harness or are you going to splice all the wires? Does your car have a premium sound system? Are you going to run an amplifier now or later on in the future??

to install this unit in your car........as a beginner i would strongly recommend buying a aftermarket radio harness (this harness will attach to the wire plug in your factory deck simply unhook the factory player and attach this harness to the plug you just pulled out of the factory unit) once this harness is installed on the factory plug it will be a simple colour match (just attach wires to pioneer wires IE. red - red, white - white........once all the wires are attached install in dash recommend buying a mounting unit for this net part it will hold the deck in place in your dash...........after that is done install your pioneer unit push it in place apply power by turning car on..........pioneer deck should turn on and work if it does not turn right on look for a source button on the pioneer unit and hold it down till the unit turns on
good luck
hope i was able to help

Display the time by pressing the Clock button below the 1+2

Adjust the hour by holding Clock and press 1 as many times as necessary.

Adjust the minute by holding Clock and press 2 as many times as necessary. Seconds start at 0 when you release the clock button.

if you have a wire harness from the original install then they are 99% of the time just color coded or you can order a replacement manual from there website http://parts.pioneerelectronics.com/model.asp?modelNum=KEH2200QR

Here is the contact us page from Pioneer tell them your problem and they should be able to send you a new face! http://www.pioneerelectronics.com/PUSA/AboutPioneer/Contact+Us

depends on the kind of car, if there is a "CAN" around it then there is a metal cahe that you need to slide 2-4 removal tools in the sides to remove it, you can use any think metal tabs abought 3-4 in long as removal tools,

if its an ISO DIN mount there are screws holding it in from the sides.

if this doesnt help much can you tell me the make and model of the car?

use your user guide to read the problem related to error 11 .. most probably your wire connecting your changer witht he head uint is either cut or not functionall ... hope that answers the question