IBM AT/370 Manual To Operations page 57

SECTION 4. PROBLEM
DETERMINATION PROCEDURES
Contents
Problem Determination Procedures . . . . . . . . . . . . 4-3
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Symptom Index . . . . . . . . . . . . . . . . . . . . . . . . 4-5
Diagnostic Testing . . . . . . . . . . . . . . . . . . . . . . 4-6
Problem Determination Procedures 4-1