Vehicle battery was disconnected for extended period of time and now radio will not play. What is procedure to activate radio ????????? This is a 99 audi a4 am-fm cd factory radio

Probably not, perhaps unless the battery has been disconnected for an extended time...

Relearn procedure isn't usually complex and generally there is a period of idling until the engine is fully warmed and then without switching off driving at various speeds for about 20 minutes. When the engine has fully cooled the initial relearning is complete. Learning will continue for the life of the ECU.

Probably shorted put somewhere, making a connection and draining your battery.

Hi,

The radio/ cd unit, for your model Jeep, has a built in security code. When disconnecting the the battery it activates the security. The reason for this is to discourage someone stealing the radio, as it renders the unit useless. To re-activate the unit you will have to enter a pin number, which should be supplied with the vehicle when bought from the dealership ( check in your operating manual). If you don't have the pin number, contact your Jeep dealer, who can supply the required pin code. Usually the dealer will re-activate your radio/cd unit free of charge.

Best of luck

When you disconnect your battery and then reconnect it again, it disables the radio. This is an anti-theft protection for your car radio.
The enable your radio the activation code is in your vehicle owner's manual. If you do not have this code you need to go to your Renault service centre and get them to enter this code for you.

When you disconnect your battery and then reconnect it again, it disables the radio. This is an anti-theft protection for your car radio.
The enable your radio the activation code is in your vehicle owner's manual. If you do not have this code you need to go to your Holden service centre and get them to enter this code for you.

When you disconnect your battery and then reconnect itagain, it disables the radio. This is an anti-theft protection for your carradio.
The enable your radio the activation code is in your vehicle owner's manual. Ifyou do not have this code you need to go to your Ford service centre andget them to enter this code for you.

If you had a recent battery change or your battery ran down and had to be recharged. The see below.

If you have a theft deterrent system, then the radio has a small chip that will shut the radio down if the power to the radio (battery) is interrupted for longer than 30 minutes. The radio has a capacitor that holds the charge on the chip for a timed period and when that charge leaks off, the chip forgets it's instructions on how to operate the radio. This is so that if the radio is stolen, then it will not operate. Usually when you do work on the vehicle that will leave the battery disconnected for more than 30 minutes, you would clip a 9V battery across the leads to maintain the charge on the radio. You are going to have to take the vehicle to a dealer that has the ability to re-program the radio, as they are generally the only people authorized to have the programming equipment. The cost is about 25 bucks

Some radios have an antitheft feature built in. When the power is disconnected (like in replacing a battery or if the radio was removed or stolen from a car) then you have to enter a code to activate it. Call the dealer and ask if they can help you with the code and procedures. Your owner's manual should have the procedure listed in it but the code should have been in the papers that came with your car when it was new. Again the dealer is your best bet. They will need your vehicle VIN and maybe even the radio serial number. There are some web sites that offer to sell you radio codes but I have had good luck with the dealers giving me them free.

In my personal opinion, electrical current recharging, unattended for a long period of time, backflowing through a circuit not designed for it with the proper fuses and protection, is asking for trouble. Wouldnt it be better to disconnect the battery, and have it fully charged when you get back? The downside is that you will lose radio code and check engine history, but if the check engine light is not on, you havent lost much.

UNIT HOUSING REMOVAL

1. Disconnect battery. This must be done to prevent accidental air bag deployment.
2. Using an A/C recovery unit, remove all R-134a refrigerant from the A/C system.
3. Remove air cleaner hose and air distribution duct from the engine.
4. Drain the engine cooling system.
5. Disconnect heater hoses at the dash panel. Plug the heater core inlet and outlet tubes to prevent anti-freeze from spilling on the vehicle interior during removal. If an appropriate plug cannot be found pull back carpet and use caution when removing unit. Keep the heater tubes elevated to prevent spillage of coolant.
6. Remove both A/C lines from expansion valve. Use special tool 7193 to disconnect quick connectors on A/C lines. Refer to A/C line removal in this section for complete procedure. After removing lines cap the expansion valve openings and the A/C hose openings. This will prevent any dirt or moisture from entering the refrigerant system during servicingCAUTION: The lubricant used in this air conditioning system absorbs moisture readily (similar to brake fluid) Do not leave any portion of the system open for extended periods of time.
   
7. Remove the three retaining nuts from the studs. These studs project through the dash panel into the engine compartment.
8. Remove right and left instrument panel end caps. These caps are held in place by a series of clips.
9. Remove right and left interior door post kick panel.
10. Remove right side bezel from instrument panel