Using COUNT Function On Multiple Columns With GROUP BY Restrictions

Consider the following dataset:

COL1 | COL2 | COL3 | COL4
1 | FD | DR. A | Y
2 | FD | DR. A | Y
3 | FD | DR. A | N
4 | FD | DR. A | Y
5 | FD | DR. A | Y
6 | PF | DR. A | Y
7 | FD | DR. B | Y
8 | PF | DR. B | N

Consider the script below:

SELECT
COL2, COL3, COUNT(COL1) AS TOTALS
FROM CASES
GROUP BY COL2, COL3
ORDER BY COL3, COL2

The script above produces the following output:

COL2 | COL3 | TOTALS
FD | DR. A | 5
PF | DR. A | 1
FD | DR. B | 1
PF | DR. B | 1

I need to add one more column to the script that counts records with 'Y' in COL4 for each COL1 category (FD, PF). The final dataset would look like this:

COL2 | COL3 | TOTALS | NEWCOL
FD | DR. A | 5 | 4
PF | DR. A | 1 | 1
FD | DR. B | 1 | 1
PF | DR. B | 1 | 0

I am having a hard time trying to use COUNT() on multiple columns with the GROUP BY restrictions that exist.