Why won't my wipers stop in my 2001 suburban?

First step is to open you hood and disconnect the negative battery terminal. Under the hood, on the firewall just below the motor wiper there is a square box that contains the module for the wiper's speed and delays. In the front of the box locate the bolts that hold the cover (usually are hexagonal), Remove the plug connection on side, then remove the circuit board, it just comes out. Visually inspect the board for cracked or loose connection or solderings, Some fissures or cracks may be not visible at all as they are under the soldered points. Clean the entire board with electronic spray cleaner (can be bought at any automotive store). With fine point soldering iron go over every terminal just touching them very briefly, you will be able to see the quick remelting of the soldering, do it with patience and plenty of good light, be careful not to touch plastic parts and wait until your soldering gun is hot. After you have gone over all the points you were able to touch, get a fine sand paper (the black kind) and sand gently the contacts on the two spring like contacts, try not to bend them (the contacts may be at different levels, that is normal). Replace Board very carefully it must go without putting pressure as putting excessive pressure may crack it. Replace connection and cover and tighten it gently. Connect battery. Start and test it, it should be working fine again.