1998 Honda Civic Keyless Entry/Radio Issues?

I have a 1998 Honda Civic EX coupe. I had an after market radio installed when I got the car and had no problems with it. About a year ago I upgraded my after market radio to a Kenwood KDC-152. My radio started going into "Protect" mode. I was able to do a hard reset and it started working. But now it remains in protect mode.M y keyless entry happened to go out shortly around the same time I started having radio issues. My original Honda radio is dropped down in my dash so I could keep my keyless entry. So I figured something happened to that, but it is still working and is still fine. So I checked my fuses which none of them were blown. I pulled the radio out and all the wiring is still intact and looks good. I tried to reprogram my keyless entry. I did the cycle of the locks and it was clicking in the doors, but nothing. The remote works and it still beeps like it should be unlocking but the doors don't lock or unlock. The interesting thing is that my check engine light came on around the time my doors and radio stopped working. My mechanic checked it but couldn't figure out what was wrong with it, and informed me that my distributor cap needed replacing. So do to not having money the check engine light has remained on. Until today when I tried to reprogram my keyless entry remote. During the clicking of the remote the check engine light went off. So my question… Has anyone heard of this and what can I do to fix it and what is the problem? I really miss listening to music.

Check all connections to the battery, and maybe replace the alarm remote battery.

If this all started around the same time remove the radio and double check the ISO connection (2 X 8 wire blocks) one will have 8 thin wires for the speakers. Just plug together
The other one will have 3 thick wires and 2 or 3 thin ones. Make sure the colour match across the joint
The 3 thick ones are Switched feed, Permanent feed and earth. One of the thin ones is Electric Aerial Trigger, Another one will be the radio lights On/Off with the car lights
Cars have been know to throw out Central Locking if radio not wired correctly so check that first

Andy C