All Doors Fail to Lock From Any Switch

Tests 1 - 4:

Tests 5 - 6:

SYMPTOM
ALL DOORS FAIL TO LOCK FROM ANY SWITCH

POSSIBLE CAUSES
- Door lock relay output circuit short to ground
- Key-in ignition switch shorted
- Key-in ignition switch sense circuit short to ground
- Central timer module - door lock open
- Central timer module - key-in ignition switch shorted