silverfoxdan

I need to add additional keys for family members. I have one original and working key for my 2009 Avalanche.

Everything I read says to put the working key in the ignition, turn it past ACC to the ON position then wait for the dash security symbol (car with a lock) to go off, then, remove the working key and within 5 seconds, place the new key in the ignition, turn it ON and wait for the system to recognize it (car with lock goes off). The second option was to actually start the truck with the working key then turn it off then place the new key and wait for the car-lock symbol to go off.

I have tried both approaches but neither one works... car-lock never vanishes and it tells me to service the security system. I have tried two new keys... same result.

I have also read about the method of leaving the key in the ignition for 10 minutes three times but I am reluctant to try this one for fear of deprogramming the one working key. I think this approach was if you had no working key at all.

Anything unusual about the 09's for adding another key?

tech2

if this is a Canadian vehicle...it requires 2 programmed keys to begin the process.....
try to fake it out by using the one key 2x
insert key...key to run,...remove key and move it arms length away from ignition...insert same key...turn to run....remove....insert new key...turn to run...remove key. see if the new key works.

silverfoxdan

Thanks for the reply tech2. Truck assembled in Mexico with a 3GN starting the VIN. Even so, I tried the key approach you suggested but it did not work. Very much appreciate the suggestion though.

tech2

have the dealer program it then.

What I meant was; was it made/sold originally for the Canadian market. If yes, it will have different programming. the speedo would be in km if it was.

silverfoxdan

Resolved: Seems the eBay seller listed the '09 Avalanche as compatible with his keys in error.

I purchased one from our local ACE hardware store and another key from Amazon and they both program perfectly using the method I first described.

The "key" to all this is the blank MUST have the "+" sign on it. BTW, Home Depot and Walmart cut these keys for free.

tech2

fyi...don't trace old keys...ie Walmart and home depot. have the new key cut from a key code provided by a dealer or locksmith. Tracing old worn out keys could not work in the ignition cylinder....be a waste an expensive transponder key

the + sign on the blade means its a transponder key.

silverfoxdan

Thanks for the input. I really can't find an official statement on the + key issue but it is not as simple as some people might guess. Obviously, the keys that I have a + sign must have the chip inside or they would not work. I also took apart the keys without a + sign and... they both have transponder chips inside. That said, I believe it relates more to a frequency or resonance set than the presence of a transponder chip.

Walmart and home depot have both updated their key making equipment from the dark ages and they are very accurate. I am five for five (two wrong transponder keys and three good keys) using my only working key ( working in the ignition as well as the doors) as the master at both these places. I did all this without the extra cost of going to a dealer or a locksmith. A gamble? well, I got a genuine blank GM key off amazon for 14 bucks so none of this was a big gamble.

Could I go to a dealer or locksmith and spend extra money? sure but that isn't what most people who pay for all the gas Avalanches use normally do. I love my gas guzzler by the way.

tech2

the issue in tracing a worn key....you trace the worn pattern onto the new key. cutting from a code puts the correct pattern on the key. many people have a problem will the key not rotating in the cylinder due to the worn key not fitting the tumblers. a new key traced to an old key will not fix their problem.

+ means its a passkey 3 theft system. After market keys...anything's possible.