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Home >> Mazda >> 2000 >> Protege ES, Automatic >> Repair and Diagnosis >> Body & Frame >> Door Locks >> Anti-Theft/Keyless Entry Systems >> System Tests >> Test No. 1: One Or More Diagnostic Functions Inoperative >> Possible Causes
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Possible Causes

To identify possible sources of diagnostic function problems, see DIAGNOSTIC FUNCTIONS  table.

DIAGNOSTIC FUNCTIONS

Affected System Possible Causes
Horn Horn Circuit Malfunction
Keyless Control Module
Wiring Harness Problem Between Keyless Control Module & Horn Relay
Headlights Headlight Circuit Malfunction
Keyless Control Module
Wiring Harness Problem Between Keyless Entry Module & Headlight Relay
Hazard Lights Hazard Light Circuit Malfunction
Keyless Control Module
Wiring Harness Problem Between Keyless Control Module and Hazard Lights Or Flasher Control Module
Door Locks Door Lock Linkage Malfunction
Door Lock Switches Door Lock Switch Circuit Malfunction
Keyless Control Module Door Unlock Signal Keyless Control Module
Wiring Harness Problem Between Keyless Control Module and Door Lock Control Module
Driver's Side Door Key Cylinder Switch Driver's Side Door Key Cylinder Switch Or Circuit
Keyless Control Module Door Lock/Unlock Signal Keyless Control Module
Wiring Harness Problem Between Keyless Control Module and Door Lock Control Module