After changing the battery the sound system is locked and I don't know the code number to unlock

Your keyless remote is equipped with 2 different systems. There is the RF system (long range, lock control only) and the IR system (short range, locks and convenience features such as remote window roll-up and roll-down). It sounds like your RF system isn't working. The only way to test the system, that I know of, is with a Mercedes scanner. It is likely a bad remote.

read qowners manual for exact number of times... but put key in ignition turn on and off between 7 and ten times..... locks will actuate! hit lock button on remote... remote is then set

Sounds as if the van lost that code for the PATS(Passive Anti-Theft System) key. You will have to have it programmed again. Some well equipped key and lock shops may be able to do this, otherwise off to the dealer.

Hello Jaclyn... Your Camry has an "engine immobilizer" designed to prevent "hot-wire" starting incorporated into the anti-theft system...This was standard on the XLE, & an available option on the LE. When the battery cable came off the immobilizer lost it's memory & is not reckoning the chip in the key. Try locking and closing all the doors. Then unlock the drivers door with the key. Repeat this several times, also tap the brake & gas pedal. If this does not help the dealer will have to reset it by the vehicles VIN number.
I hope this information is helpful.

Press station 1 and 6 and turn the ignition key to on position but donot start the vehicle, you will see the unlock code flashing, note the number that is your radio code, read your vehicle manual and insert code to unlock.

Just wait one hour and it will reset and you can then try it again. You have ten chances. If for some reason you start to put it in wrong again, just put in any digits as if that were the 5 digit code. If you don't complete, it will lock again and you will need to wait another hour. I hope this helps and good luck.

This is a anti-theft device built into your radio designed to foil robbers. When the radio looses power, the radio locks up. This makes the radio worthless on the black market. The thieves know this and don't steal it as a result. Your owners manual tells you to clear the code if there will be a power loss (changing the battery). There may not be a recovery procedure.

In the GM (1995) version of this system, there is no recovery (if there were, what would be the point of the system?). I don't know the specifics of the Volvo system. You may want to talk to your dealer before you replace your radio. I am sure you will have to prove ownership of the vehicle.

Thanks for your question @ FixYa.com this morning.

This is a problem with the Theft-Loc system. I believe you will have to take it to the dealer to have the radio unlocked. I found this procedure on the web, but I don't know if it will work. Good luck.

1. Turn the ignition ON (The radio should display "LOC")

2. Hold down the Radio Presets 2 and 3 buttons for six seconds

3. The radio display changes from LOC to a three-digit number. Write this number down. You now have fifteen seconds to complete the next step.

4. Press the AM/FM button

5. The radio display changes to another three-digit number. Write this number to the right of the first one.

6. You now have a six-digit number, the first three digits are from STEP 03 and the last three digits are form STEP 05

7. Call 1-800-537-5140

8. Press 1 then # (pound). You'll hear "Invalid Code, try again"

9. Press 139010 or 106010 or 206010 or 202107 then # (pound). You will be asked to enter your four or six digit code followed by *

10. Enter the number from STEP 6 then *

11. Listen to the four-digit number and write it down. It will be repeated twice

12. Turn the ignition ON (The radio displays LOC)

13. Use the MN and HR buttons to enter the code from STEP 11

14. Press the AM/FM button. The radio display changes to "SEC". Your radio is now "un-locked" and usable.

Firstly, pop a new battery in the fob.
Now we can enter the EKA.
Close all the doors.
Turn the key in the driver door lock to the unlock position and hold there for at least 5 seconds until the alarm sounds once. Then return to centre - always ensure you return to centre and do not delay more than 10 seconds between turns, or hold in the position for more than 5 seconds or you will reset to the start. Turn to full extent of travel.
1st Digit turn to unlock the number of times specified.
2nd Digit turn to lock the number of times specified.
3rd Digit turn to unlock the number of times specified.
4th Digit turn to lock the number of times specified.
Finally turn to unlock once more. If it is correct a double bleep will sound (single bleep is incorrect code)
You now have a 5 minute delay - don't open any doors. The anti-theft indicator will continue flashing once every 2 seconds for the five minute period. When this goes out, open the door and start within 30secs.
After 3 failed attempts, the security system invokes a delay period of 10 mins during which the system will not accept any further attempts to enter a code.

Well, you may not need to take it to a dealer if you have the EKA code.
Firstly, pop a new battery in the fob. Get the vehicles battery charged up or changed.
Now we can enter the EKA.
Close all the doors.
Turn the key in the driver door lock to the unlock position and hold there for at least 5 seconds until the alarm sounds once. Then return to centre - always ensure you return to centre and do not delay more than 10 seconds between turns, or hold in the position for more than 5 seconds or you will reset to the start. Turn to full extent of travel.
1st Digit turn to unlock the number of times specified.
2nd Digit turn to lock the number of times specified.
3rd Digit turn to unlock the number of times specified.
4th Digit turn to lock the number of times specified.
Finally turn to unlock once more. If it is correct a double bleep will sound (single bleep is incorrect code)
You now have a 5 minute delay - don't open any doors. The anti-theft indicator will continue flashing once every 2 seconds for the five minute period. When this goes out, open the door and start within 30secs.
After 3 failed attempts, the security system invokes a delay period of 10 mins during which the system will not accept any further attempts to enter a code.