Introduction
The Power Probe III is a versatile automotive diagnostic test tool designed for comprehensive electrical system testing. It integrates multiple functions, serving as a digital voltmeter, and capable of measuring AC/DC current and resistance. This tool is engineered to simplify complex automotive electrical diagnostics, providing circuit breaker protected power and ground to activate components directly.

Figure 1: Power Probe III with included accessories.
Setup
To begin using your Power Probe III, connect it to a 12-24 volt vehicle battery. The tool utilizes the vehicle's own battery as its power source. The included 20-foot power cable allows for extensive reach, enabling you to access test points throughout most vehicles, including larger trucks and trailers.
Connecting to Power Source:
- Connect the red clip to the positive (+) terminal of the vehicle battery.
- Connect the black clip to the negative (-) terminal of the vehicle battery.
- Ensure connections are secure to prevent intermittent power.

Figure 2: Proper connection of the Power Probe III to a vehicle battery.
Optional Power Port Adapter:
For convenience, the Power Probe III can also be powered via a 12-volt power port adapter (cigarette lighter socket). This is useful for quick checks inside the vehicle cabin.
Video 1: Official product overview and demonstration of the Power Probe III's features, including power and ground supply, cable length, and available kits. This video also shows the 12V power port adapter in use.
Operating Instructions
The Power Probe III is designed for intuitive operation, allowing technicians to quickly diagnose electrical issues.
Digital Voltmeter Function:
Once connected to a power source, the digital display on the Power Probe III will show the voltage at the probe tip. This allows for rapid voltage checks at any point in the circuit.

Figure 3: Digital display showing voltage reading.
Power and Ground Supply:
The rocker switch on the tool allows you to instantly supply circuit breaker protected power or ground to a component. Push the switch forward to supply positive voltage, or backward to supply ground. This feature is crucial for activating components for testing without needing to run separate wires.

Figure 4: Power Probe III in use, testing an automotive component.
Auxiliary Ground Lead:
For bench testing components that require a constant ground, utilize the auxiliary ground lead. This provides a stable ground connection for accurate testing.
LED Headlamps:
The Power Probe III is equipped with two bright LED headlamps to illuminate your work area, especially useful in dimly lit engine bays or under dashboards.
Maintenance
To ensure the longevity and optimal performance of your Power Probe III, follow these maintenance guidelines:
- Cleaning: Wipe the tool and cables with a clean, damp cloth after each use. Avoid using harsh chemicals or abrasive cleaners.
- Storage: Store the Power Probe III and its accessories in the provided carrying case in a dry, cool environment, away from direct sunlight and extreme temperatures.
- Probe Tip: The 4mm removable probe tip can be replaced if it becomes damaged or worn. Ensure it is securely fastened before use.
- Cable Inspection: Regularly inspect the power cables and clips for any signs of wear, cuts, or damage. Replace damaged cables immediately to prevent electrical hazards.
Troubleshooting
This section provides solutions to common issues you might encounter with your Power Probe III.
No Power/Display Not Lighting Up:
- Verify that the red and black clips are securely connected to the correct terminals of a functioning 12-24 volt vehicle battery.
- Check the vehicle's battery voltage to ensure it is within the operating range of the Power Probe III.
- If using the 12-volt power port adapter, ensure the vehicle's power port is active and functioning.
Circuit Breaker Tripping Frequently:
- This indicates a short circuit or an excessive current draw in the component or circuit being tested.
- Disconnect the Power Probe III from the circuit and investigate the component or wiring for shorts before re-testing.
- The Power Probe III's internal circuit breaker is designed to protect both the tool and the vehicle's electrical system.
Diagnosing a Blown Fuse with Power Probe III:
The Power Probe III can quickly identify if a fuse is blown and if there's a short circuit on the line. By probing both sides of the fuse, you can determine if power is present and if the circuit is grounded out.
Refer to the official Power Probe website or support channels for detailed troubleshooting videos and guides.
Specifications
| Feature | Detail |
|---|---|
| Brand | Power Probe |
| Model | PP319FTCBLU |
| Power Source | Corded Electric (12-24V DC Vehicle Battery) |
| Measurement Type | Voltmeter (Digital) |
| Item Weight | 2.1 Pounds |
| Product Dimensions (L x W x H) | 7.5 x 4 x 10.25 inches |
| Cable Length | 20 feet (jumper lead set) |
| Additional Features | Bad ground indicator, short circuit indicator, continuity tester, relay and component tester, two bright LED headlamps. |
Warranty and Support
Power Probe products are manufactured to high standards. For specific warranty information, please refer to the documentation included with your product or visit the official Power Probe website. Protection plans are available for extended coverage.
For technical support or inquiries, please contact Power Probe customer service. You can also find additional resources and product information on the Power Probe Store on Amazon.





