I found some information for you. It would appear from this internet article that your 2005 Odyssey should be using a sidewinder style key. These are the keys which are cut into the sides and not like what we think of a normal key. They also do not have the fob built into them. Vehicles which use this key are:
- 2005-2012 Odyssey
- 2005-2011 Element
- 2003-2005 Accord
- 2006-2012 Civic
- 2007-2012 CRV, Pilots and S2000's
Most of these keys have to be done at the dealership, but some can be cloned (much cheaper). On the key, there'll be a letter stamped on it. Here is the key:
Here are the codes and which can be cloned and which have to be programmed:
- V - V keys must be programmed.
- H - H keys must be programmed.
- S - S keys can be cloned.
- F - F keys can be cloned.
- T5 - T5 keys can be cloned.
- Blank - If the key has no markings it can be cloned.
If the key is one which can be cloned, the parts department can do this for you. This is a lot quicker than getting it programmed into your vehicle. To get it programmed, you'll have to take it to the service department and have all of your keys programmed. This is added time and expense.
Either way, if you lose your key, things become tough. If you lose your key you can get a temporary key made which is not programmed. There is a procedure called the "brake code" which can be entered into your vehicle to allow you to start your vehicle and drive it basically once (allows you to get it to the dealership for reprogramming). Here is the procedure for that (also from the above website):
Your Honda is equipped to accept a procedure which will temporarily by-pass the immobilizer and allow you to start the vehicle temporarily. This will allow you to drive to Honda Mall of Georgia to get a programmed key. Of course to do even this you will still have to get a temporary key cut just to turn the ignition and proceed with the by-pass.
Once we have cut the temporary key for you, give us the VIN# for your vehicle. From there we can access Honda's database and obtain a "PCM brake code". The PCM brake code is a 5 digit code. The procedure for entering the brake code is a series of turning your ignition to the ON position then tapping your brake or pulling your emergency brake handle up and down for a fixed count. For example, if the first digit in the brake code is a 4. Release your parking brake and turn your ignition to the ON position. Now set and release your parking brake 4 times and turn your ignition to the LOCK position. The first digit is now set. Repeat this procedure for the remaining 4 digits. After you enter the 5th digit and turn the ignition to the LOCK position, the immobilizer indicator blinks three times and then goes off. You can now start the engine with the temporary key.
NOTE: This procedure is only a temporary fix. When you start the engine with the temporary key, the immobilizer system indicator comes on and stays on while the engine is running. Also when you turn the ignition to the LOCK (0), the indicator does not blink five times as it normally would.
Start the engine within 10 minutes...or you must repeat the procedure entirely.
I'm not entirely sure where you get the brake code from, but would imagine your dealership can give it to you if you have the VIN, registration, and ID.