Defibrillators · AED family

ZOLL AED 3: troubleshooting and error codes

The ServiceForge knowledge base holds 24 documented symptoms for the ZOLL AED 3, with 29 ranked causes, 33 diagnostic checks with test points and expected values, and 0 error codes. Each symptom below shows its causes and the first check; the rest is one connection away. Connect ServiceForge to your AI

Symptoms

Audio recording playback not functioning

Voice prompts and events from patient rescue not audible or playable in RescueNet Code Review software

Ranked causes

1. Audio recording setting disabled on AED (occasional)
2. RescueNet Code Review software version incompatible or incorrect file selected (occasional)
3. Clinical Event data not transferred or corrupted during USB export (rare)

First check

CRD files present on exported USB drive

Test point: Computer File Explorer, USB drive root directory
Expected: CRD files present from previous USB test export

2 more checks with pass and fail actions, 4 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Beeping noise when AED is off caution

AED emits beeping sound while powered off.

Ranked causes

1. Defibrillation pads cable not properly plugged in (common)
2. Internal error after self test failure (occasional)

First check

Inspect defibrillation pads cable connection

Test point: Patient cable connector
Expected: Cable fully seated and secure

1 more check with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

NO SHOCK DELIVERED message displayed patient safety

AED indicates shock was not delivered when expected.

Ranked causes

1. Shock button not pressed (occasional)
2. Internal error with shock delivery circuit (rare)

First check

Verify Shock button is pressed when prompted

Test point: Shock button
Expected: Button depressed within 30 seconds of charge-ready tone

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

USB file export not functioning

USB device icon not appearing in status bar, or files not transferring to USB drive during data export procedure

Ranked causes

1. USB Flash Drive not properly inserted or not recognized by device (common)
2. Data transfer incomplete or interrupted (occasional)

First check

USB device icon appearance in status bar

Test point: Status bar at bottom of display screen
Expected: Blinking USB device icon appears and switches to steady status

4 more checks with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

ANALYSIS HALTED; KEEP PATIENT STILL message displayed patient safety

AED halts ECG analysis and prompts to keep patient still.

Ranked causes

1. Patient movement during ECG analysis (common)

First check

Ensure patient is immobilized during analysis

Test point: Patient position and stretcher/vehicle movement
Expected: Patient completely still, analysis proceeds without interruption

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

ATTACH CORRECT DEFIB PADS message displayed patient safety

AED indicates incompatible or incorrect defibrillation pads are attached.

Ranked causes

1. Incompatible defibrillation pads attached (occasional)

First check

Verify correct pads are attached

Test point: Pads identification
Expected: Compatible pads recognized, message clears

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Battery connector damaged or corroded

Battery housing connectors show damage, excessive wear, corrosion, or other conditions preventing proper electrical contact.

Ranked causes

1. Connector degradation or corrosion (occasional)

First check

Inspect battery connectors

Test point: Battery pack connector pins and housing
Expected: Connectors free of damage, corrosion, and excessive wear

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Battery housing cracked or damaged

Battery pack enclosure has cracks, breaks, or other physical damage affecting structural integrity or electrical safety.

Ranked causes

1. Physical damage to battery housing (rare)

First check

Inspect battery housing

Test point: Battery pack enclosure
Expected: Housing free of cracks and damage

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Battery installed past expiration date

Battery pack has exceeded its install-by date and must be replaced before the AED can be used.

Ranked causes

1. Battery past install-by date (common)

First check

Check battery install-by date

Test point: Battery pack label
Expected: Install-by date has not passed

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Battery not properly seated

Battery is not correctly positioned in the battery well, preventing proper connection and operation of the AED.

Ranked causes

1. Battery incorrectly installed (common)

First check

Inspect battery seating in well

Test point: Battery well
Expected: Battery fully seated and secure

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

CHANGE BATTERY message displayed patient safety

AED screen displays CHANGE BATTERY prompt.

Ranked causes

1. Battery pack depleted or near end of life (common)

First check

Verify battery replacement resolves message

Test point: Display screen
Expected: CHANGE BATTERY message no longer appears

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

CHECK PADS message displayed patient safety

AED screen displays CHECK PADS prompt.

Ranked causes

1. Pads not properly attached or connected (common)

First check

Verify pads are properly attached

Test point: Pads connectors
Expected: Pads seated firmly and message clears

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Defibrillation pads expired or disconnected patient safety

Defibrillation pads are either past their expiration date or not properly connected to the AED, preventing proper electrode function.

Ranked causes

1. Pads expired or not connected (common)

First check

Verify pads are within expiration date

Test point: Defibrillation pad package
Expected: Expiration date has not passed

1 more check with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Display window or screen damaged

Front panel display has cracks, damage, or other defects that affect visibility or operation of the AED screen.

Ranked causes

1. Physical damage to display (occasional)

First check

Inspect display for damage

Test point: Front panel and screen
Expected: No cracks or visible damage

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Electrode cable damaged high voltage

Defibrillation pad cable has visible cracks, cuts, or exposed or broken wires that compromise electrode function.

Ranked causes

1. Cable physical damage (occasional)

First check

Visual inspection of electrode cable

Test point: Entire cable length and connectors
Expected: Cable free of cracks, cuts, or exposed wires

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Green check does not appear in status indicator window

Status indicator window does not show green check mark during normal operation.

Ranked causes

1. Internal self-test failure (unknown)

First check

Verify green check appears in status indicator window after self test

Test point: Status indicator window
Expected: Green check mark visible

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Handle malfunction

AED carrying handle does not operate properly, is damaged, or does not function as expected.

Ranked causes

1. Handle mechanical failure (rare)

First check

Test handle operation

Test point: AED carrying handle
Expected: Handle moves smoothly and locks in both open and closed positions

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Housing damage or excessive wear

AED housing is damaged, cracked, has loose parts, or shows signs of excessive wear compromising device integrity.

Ranked causes

1. Physical damage to housing (occasional)

First check

Visual inspection of housing

Test point: Complete AED enclosure
Expected: Clean, undamaged, free of excessive wear

1 more check with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Input connectors dirty or damaged

AED input connectors are not clean or show signs of damage, corrosion, or wear that may affect electrical connections.

Ranked causes

1. Connector contamination or damage (occasional)

First check

Inspect input connectors

Test point: All AED input connectors
Expected: Connectors clean and undamaged

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

PLUG IN PADS CABLE message displayed patient safety

AED screen displays PLUG IN PADS CABLE message.

Ranked causes

1. Defibrillation pads cable not properly plugged in (common)

First check

Inspect and reseat defibrillation pads cable

Test point: Patient cable connector
Expected: Cable fully inserted and seated

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

RELEASE SHOCK BUTTON message displayed patient safety

AED (semi-automatic models) prompts operator to release the Shock button.

Ranked causes

1. Shock button held during charge phase or prematurely (occasional)

First check

Verify button is released and message clears

Test point: Shock button state
Expected: Button released, message disappears

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

REPLACE PADS message displayed patient safety

AED indicates defibrillation pads require replacement.

Ranked causes

1. Pads expired or no longer functional (common)

First check

Verify new pads resolve the message

Test point: Display screen
Expected: REPLACE PADS message no longer appears

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Status indicator blank after self test patient safety

Following completion of any self test, the status indicator does not display the green check mark, indicating the AED is not ready for use and may be defective.

Ranked causes

1. Failed self test (common)

First check

Verify AED power on and self test completion

Test point: Status indicator
Expected: Green check mark displayed

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

UNIT FAILED prompt displayed patient safety

AED displays UNIT FAILED message on screen.

Ranked causes

1. Internal self-test failure (unknown)

First check

Verify self test completes without UNIT FAILED prompt

Test point: Display screen
Expected: Self test passes, green check appears

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Community

0 fixes logged by technicians through their AI, with outcomes, for this model.

ServiceForge knowledge base record. Field-unverified unless technicians confirmed it. A teaching summary of the record, not a service manual. Export 2026-10-14.