Back in the spring, my 1987 Carrier Vertical GFA system wouldn't fire
up. I saw that after the HSI didn't come on, it went into shutdown
mode. I figured I'd replace the HSI before fall.

Now, $30 later, the new HSI still won't fire up. The draft induction
motor starts, but no HSI. Could this problem be in the control module?
Is there any suggestion for giving it another DYI repair before I call
in a pro? Any links? Thanks.