In theory there are 6!, or 6 factorial number of combinations that is possilbe with the 7th Gen radio which has 1 through 6 as pre-set keys.
So that's 6*5*4*3*2*1= 720 possilbe combinations of codes, one can always kill an afternoon working through the permutations starting with 1, 1, 1, 1, 1, 1, then 1, 1, 1, 1, 1, 2, and so on!
So yes not all radios will have unique security codes when there are only 720 combination/permutation to pick from.
Honda really should add a 7th digit, it will bring the combinations up to 5,040, a far more difficult task to perform through brute force method.
You're incorrect, sir. Your possible combinations only reflect a decrease in numbers if you are eliminating digits from the combination. In your example 1, 1, 1, 1, 1, 1 would not match the 6*5*4*3*2*1 bc in the first set you have all numbers 1-6 available to you, the second set would not allow the 1 bc you would have already used the one thus decreasing your combinations to options 2-6 and so on and so forth.
So, in essence, the factor is actually 6*6*6*6*6*6 which equal 46,656 total combinations so a 7th digit is not necessary at all.
Actually, I think he's right. Because, though I can't prove all are like this, both of my Accords have had codes with no duplicate digits in them. That is, if the code started with a "4", there were no other "4"'s. Therefore it is possibly factoral and 720 is the max combinations.
It remains a matter of opinion whether the 7th digit is necessary. The existing code is causing us enough headaches, so I can imagine it causes thieves headaches too.
Actually, it's supposed to be 6^6 so CrashFive is right. It's 6 positions with 6 different possibilities. If it's 6 unique, non-repeating numbers then Aviography is right.
As it turns out, I was wrong and CrushFive was right.
I had to change battery yesterday, and realized two of the 6 digits of the radio code were repeated twice.
So the good news is that the number of permutations is 6 to the power of 6 (1-6 for each of the 6 digits) as CrushFive correctly stated, a very large number more than enough to frustrate someone attempting to use the brute force method by trying every combination.