The OBDMonster PS100 Pro Automotive Circuit Tester is built for technicians, mobile mechanics, automotive electricians, fleet maintenance teams, and serious DIY users who need a faster and more reliable way to diagnose vehicle electrical problems. It combines multiple electrical diagnostic functions into one compact professional tool, helping users test power, ground, resistance, continuity, frequency, diode condition, and circuit integrity.

Automotive electrical faults are often difficult to locate. A blown fuse, dead light, intermittent accessory failure, weak ground, damaged wire, bad relay, or short circuit can waste hours of diagnostic time. The PS100 Pro helps users move from guessing to confirmed testing by showing clear electrical data directly at the circuit.

Six Work Modes for Complete Electrical Diagnostics

The OBDMonster PS100 Pro is designed with six work modes to cover the most common automotive electrical diagnostic tasks. Instead of switching between multiple tools, users can perform voltage testing, signal testing, resistance testing, diode testing, continuity testing, and frequency testing with one circuit probe.

Quick Self-Test and Polarity Identification

Correctly identifying circuit polarity is one of the first steps in automotive electrical troubleshooting. The PS100 Pro helps users quickly identify whether a test point is positive, negative, or open. This is useful when checking fuses, switches, connectors, sensors, lights, motors, relays, and power supply circuits.

The color-based display makes testing easier to understand: a red indication helps identify positive voltage, while a green indication helps identify negative or ground condition. This gives technicians faster feedback when diagnosing power supply and ground faults.

Continuity Testing with Buzzer Feedback

Continuity testing helps confirm whether a wire, switch, connector, fuse, relay path, or circuit section is complete. The PS100 Pro provides fast continuity diagnostics with buzzer feedback, making it easier to verify circuit integrity without constantly watching the screen.

When resistance is low, the tester can indicate good conductivity with an audible buzzer. When resistance is too high or the circuit is open, the buzzer will not sound. This makes it practical for quickly checking wiring harnesses, terminals, grounds, switches, and connectors.

Voltage and Signal Testing for Advanced Diagnosis

The PS100 Pro can help users view electrical signal behavior, including maximum voltage, minimum voltage, frequency, and duty cycle information. This is useful when checking pulsed circuits, control signals, sensor-related wiring, and electrical components that do not simply stay on or off.

For technicians dealing with intermittent faults, voltage drops, unstable signals, or abnormal circuit behavior, the ability to observe signal-related data helps improve diagnostic accuracy and reduce unnecessary part replacement.

Resistance Testing for Circuit and Component Inspection

Resistance testing helps users evaluate wires, switches, components, and circuit paths. The PS100 Pro can be used to check resistance values and identify possible high-resistance faults, poor connections, damaged wires, or faulty electrical components.

This function is especially useful when diagnosing wiring harness problems, corroded connectors, switch failures, motor circuits, sensor circuits, and circuit paths that appear connected but do not perform correctly under load.

Frequency Testing with 180° Screen Rotation

The PS100 Pro supports frequency testing for signal-related diagnostics. It can help users check maximum voltage, minimum voltage, frequency, and signal timing data. This is useful for circuits that operate with pulses or changing signal patterns.

One of the most practical design upgrades is the 180° screen rotation function. Automotive testing often happens under dashboards, inside door panels, near fuse boxes, around engine bays, or behind components. The rotating display allows users to read the screen more easily from different working angles, reducing awkward hand positioning and improving efficiency.

Component Activation and Power Probe Testing

The OBDMonster PS100 Pro can be used as a power circuit probe to activate supported automotive electrical components. By applying power or ground through the probe tip, technicians can test whether a component responds correctly before replacing parts or tracing deeper into the wiring harness.

This function is useful for checking many supported loads such as lights, relays, motors, solenoids, fans, pumps, horns, and other electrical accessories. It helps determine whether the issue is caused by the component itself, the wiring, the fuse, the relay, the ground, or the control signal.

40FT Cable for Cars, Trucks, RVs, and Trailers

The PS100 Pro is equipped with a long cable setup designed for real repair environments. With a 20FT main cable and 20FT extension cable, users get up to 40FT total working reach. This makes it easier to test circuits at the front, rear, interior, engine bay, trailer connection, or cargo area without constantly moving the power source.

The long cable is especially useful for larger vehicles such as pickup trucks, commercial vehicles, RVs, vans, trailers, and fleet service applications.

Built for Common Automotive Electrical Problems

The PS100 Pro is designed for the electrical issues technicians face every day. It helps users confirm whether a circuit has power, ground, signal, continuity, resistance, diode function, or frequency output before replacing parts or disassembling more components.

• No-start electrical diagnosis: Check power supply, ground condition, fuses, relays, and starter-related circuits.
• Blown fuse troubleshooting: Help identify short circuits or abnormal electrical paths.
• Lighting repair: Test headlights, brake lights, turn signals, reverse lights, and trailer wiring.
• Relay and motor testing: Activate supported relays, motors, pumps, and solenoids directly.
• Ground fault diagnosis: Locate poor ground connections and unstable electrical behavior.
• Wiring harness inspection: Check continuity, resistance, open circuits, and connector integrity.
• Signal troubleshooting: Analyze frequency, duty cycle, max voltage, and min voltage on supported signal circuits.

Key Features

Technical Specifications

Who Should Use the OBDMonster PS100 Pro?

The PS100 Pro is ideal for anyone who regularly works with automotive electrical circuits and needs fast, clear, and practical diagnostic feedback. It is especially useful for technicians who need to confirm circuit condition before replacing parts.

• Professional auto repair shops
• Automotive electrical diagnostic technicians
• Mobile mechanics
• Fleet maintenance teams
• RV and trailer service technicians
• Motorcycle and powersports repair users
• Used car inspection professionals
• Advanced DIY users and automotive enthusiasts