2-in-1 Automotive Circuit & Relay Tester – 3.5–36V Power Probe for 12V/24V Vehicles, 4/5-Pin Relay Tester

2-in-1 Automotive Circuit & Relay Tester Find Electrical Faults Faster—Without Constantly Switching Tools Tracking down a bad wire, blown circuit, poor ground, or faulty relay can turn into a frustrating guessing game. The 2-in-1 Automotive Circuit & Relay Tester combines a digital automotive power probe with built-in 4-pin and 5-pin relay testing, giving you one practical tool for diagnosing common vehicle electrical problems. Probe. Test. Diagnose. Move on. ✓ Digital voltage testing ✓ Positive / negative polarity detection ✓ Continuity & circuit checks ✓ Positive / negative output control ✓ Built-in 4-pin & 5-pin relay tester ✓ Integrated LED work lights ✓ Designed for 12V / 24V vehicle electrical systems ✓ Extra-long 4.35 m / 14.27 ft power cable FREE Shipping | 30-Day Money-Back Guarantee Stop Guessing Which Part Is Causing the Problem Electrical problems aren't always caused by the component that stopped working. The real issue could be: A missing power supply Poor ground Broken wiring Failed relay Open circuit Connection problem Instead of replacing parts blindly, use the probe to quickly check what is happening inside the circuit. The digital display gives you immediate voltage information while the integrated polarity indicators help identify positive power, negative/ground, or no voltage. One Tool. Two Essential Diagnostic Functions. Automotive Circuit Tester Use the probe for common electrical troubleshooting including: Voltage checks Positive / negative polarity detection Ground verification Continuity checks Circuit troubleshooting Short-circuit diagnosis Compatible component activation/testing The rocker switch allows positive or negative output through the probe, making it easier to test compatible circuits and low-current automotive components where appropriate. Built-In Relay Tester No separate relay tester required. Insert a compatible standard 4-pin or 5-pin automotive relay directly into the corresponding socket, select the correct relay mode, and test it from the same device. Useful for identifying problems such as: Relay failure to engage Coil failure Contact sticking Abnormal relay operation Designed for compatible 12V and 24V automotive relays. See Voltage & Polarity Instantly A bright digital screen displays real-time voltage while dedicated indicator lights simplify polarity identification. Red indicator: Positive voltage detected Green indicator: Negative / ground detected No indicator: No voltage detected That means less time moving between different meters and test tools. Send Positive or Negative Power From the Probe The integrated rocker switch lets you apply positive or negative output through the probe when performing suitable circuit tests. This can help technicians test compatible: Lights Relays Solenoids Electrical circuits Low-current automotive actuators and components Always verify the component's voltage and current requirements before applying power. Test Standard 4-Pin & 5-Pin Automotive Relays Relay problems can mimic wiring or component failures. Instead of replacing a relay just to see what happens, test compatible 4-pin and 5-pin relays directly. Switch between the appropriate relay modes and quickly determine whether the relay is responding correctly. Built-In LED Work Lights Electrical faults don't always happen somewhere easy to see. Integrated LED lights illuminate the probe area while working around: Fuse boxes Engine compartments Wiring harnesses Under dashboards Low-light repair areas No need to hold a flashlight while trying to position the probe. Extra-Long 14.27 ft Cable The approximately 4.35 m / 14.27 ft power cable gives you room to move around larger vehicles without constantly repositioning the power connection. Connect the battery clamps and reach circuits throughout much of the vehicle. Made for 12V & 24V Vehicle Electrical Systems Suitable for electrical troubleshooting on compatible: Passenger Cars | Vans | SUVs | Pickup Trucks | Commercial Vehicles | Trucks | Buses | Construction Equipment Ideal for mechanics, auto electricians, repair shops, fleet maintenance and experienced DIY users. How to Use 1. Connect to the Battery Connect the red clamp to battery positive (+) and the black clamp to battery negative (-). 2. Probe the Circuit Touch the probe to the wire, terminal, fuse, connector or circuit point you want to test. 3. Read the Result Check the digital voltage display and positive/negative indicator lights. 4. Perform Additional Testing Use the rocker switch or other supported functions when appropriate for the circuit being diagnosed. Testing a Relay Select the correct 4-pin or 5-pin mode, insert the compatible relay into the appropriate socket, and activate the relay test function. Always verify the relay type and pin layout before testing. Product Specifications Specification Details Model DW833 Circuit Testing Range DC 3.5–36V* Vehicle Systems 12V / 24V Relay Testing 12V / 24V Relay Compatibility Standard compatible 4-Pin & 5-Pin relays Digital Display Real-time voltage readings Polarity Detection Positive / Negative / Ground Output Control Positive / Negative rocker switch Work Light Built-in dual LED Power Connection Red & black battery clamps Cable Length 14.27 ft / 4.35 m What's Included 1 × 2-in-1 Automotive Circuit & Relay Tester Integrated probe Long battery power cable Red and black battery clamps External ground lead User instructions Perfect For Professional mechanics Automotive electricians Repair shops Fleet maintenance Truck technicians DIY vehicle owners Electrical troubleshooting Relay diagnosis Fuse-box troubleshooting Wiring repairs