Every now and then, I question my pumps calculations.

I have my pump set so that I can walk on the treadmill after eating supper everynight without going low. The thing is I have to walk or else I have to re-adjust my pump rates back to normal. I wasn't feeling too well last night so I skipped exercising and of course I forgot to adjust my rates. Because of my forgetfulness, my bg's ran high for a while.

So,I did a correction bolus. Then, before going to bed I tested again and it came down to 131 but, this is where I'm getting confused. My pump says Food-.000, Correction-.600u, Active-3.675u. My Endo wants me to keep my target at 125 for my night hours. So, why would my pump suggest a correction of .600u when I have 3.675 active? I ended up ignoring my pumps correction and I took some glucose tablets to keep from going low. I woke up this morning at 71.

I use a MiniMed 523, so I can only speak to that pump. I copied the following information from page 187 of the User Guide. Basically, four different calcs are used, depending on your current BG level: above target, within target range, below target, or unknown.

Bolus Wizard feature specifications There are four different formulas the Bolus Wizard feature uses to estimate a bolus, depending on your
current BG. The following formulas apply only when the carb units are in grams.
1 If your current BG is greater than your High BG Target, the Bolus Wizard feature subtracts active insulin
from the BG correction estimate, then adds this tothe food estimate to get the total bolus estimate.
However, if the result of subtracting active insulin from BG correction estimate is a negative number
(less than zero), the total bolus estimateis based only on the food estimate.
Food estimate:
Carb grams ÷ Carb ratio = Units of insulin
Correction estimate:
(Current BG - High BG Target) ÷ Insulin sensitivity - Active insulin = Units of insulin
Total bolus estimate:
Food estimate + Correction estimate = Units of insulin
2 If your current BG is less than your Low BG Target, the Bolus Wizard feature adds the BG correction
estimate to the food estimate to get the total bolus estimate.
Food estimate:
Carb grams ÷ Carb ratio = Units of insulin
Correction estimate:
(Current BG - Low BG Target) ÷ Insulin sensitivity = Units of insulin
Total bolus estimate:
Food estimate + Correction estimate = Units of insulin
3 If your current BG is between or equal to your Highor Low BG Target, the total bolus estimate is based
only on the food estimate.
Food estimate:
Carb grams ÷ Carb ratio = Units of insulin
Total bolus estimate = Food estimate
4 If you do not enter a BG, the total bolus estimate is based only on the food estimate.