First instance on how to test and avoid SQL deadlock

FirstInstance.sql

DELETE FROM [dbo].[TBL_test_temp]
DELETE FROM [dbo].[TBL_test_temp_two]

INSERT [dbo].[TBL_test_temp] ([TESTCOLUMNONE], [TESTCOLUMNTWO],[PK]) VALUES 
(N'TTTTTTTT',N'TTTTTTTTTTTTTT',1)

INSERT [dbo].[TBL_test_temp_two] ([TWOcolumnone], [TWOcolumntwo],[PK]) VALUES 
(N'AAAAAAAA',N'AAAAAAAAAAAAAA',1)


--1 - one
BEGIN TRAN;
Update TBL_test_temp set 
TESTCOLUMNONE =N'TTTTTTTT',
TESTCOLUMNTWO =N'TTTTTTTTTTTTTT'
Where PK =1
And TESTCOLUMNONE =N'TTTTTTTT'
AND TESTCOLUMNTWO = N'TTTTTTTTTTTTTT'
COMMIT;

--3 - three
BEGIN TRAN;
Update TBL_test_temp_two set 
TWOcolumnone =N'AAAAAAAA',
TWOcolumntwo =N'AAAAAAAAAAAAAA'
Where PK =1
And TWOcolumnone =N'AAAAAAAA'
AND TWOcolumntwo = N'AAAAAAAAAAAAAA'
COMMIT;