Hi,
What is the year and model number?
Here’s a [https://www.messicks.com/vendor/MTD/models/all|link] that may be of some help.
Find your model number on the page and then click on it and select the ''Electrical'' option that appears in the parts catalogue section menus on the left side of the page to get a wiring schematic.
Here’s an image for a 1997 13AL452F120 model, just to show maybe what to expect.
[image|2387725]
(click on image to enlarge for better viewing)