What's the honda pilot a13 code?

When You say "code", most people are going to think OBD-II fault codes. In the case of Your Honda Pilot displaying A13, this actually isn't a diagnostic code at all. You won't need any special equipment to read it, and You certainly don't have to be a mechanic to decipher it. It's a "Honda Maintenance Minder", where each character stands for something different. The "A" means that it's time to replace Your engine oil -- but not necessarily the oil filter. If You also had to replace the oil filter, it would show the character "B" instead. "1" indicates that it's time to rotate and check Your tires, including inflation and condition. Finally, "3" means that You're due for a transmission and transfer fluid (if equipped) change.