Universal 12V Automotive Relay Tester – LED Pass/Fail Indicator
Universal 12V Automotive Relay Tester – LED Pass/Fail Indicator
Quickly diagnose faulty automotive relays before they leave you stranded. The Universal 12V Automotive Relay Tester (Model CNBJ-707) is a professional-grade go/no-go tool designed to check the general health and proper functioning of the most common 4-pin and 5-pin car relays — all powered directly by your vehicle's 12V battery. No external power supply needed.
Made in Mainland China.
How It Works
Simply clip the tester onto your car battery, select the correct pin mode (4-pin or 5-pin), plug in the relay, and press TEST. The tester automatically:
- Verifies the relay's pin configuration against standard automotive relay layouts
- Opens and closes the relay contacts 10 times to evaluate contact closure and opening speed
- Checks contact consistency across each test cycle
- Lights a GREEN LED when the relay passes all checks, or a RED LED when a fault is detected
Key Features
- Universal Compatibility: Works with the most common 4-pin and 5-pin automotive relays
- 12V Battery Powered: Connects directly to your car battery (11V–15V range) — no extra batteries required
- Instant LED Readout: Green = Pass, Red = Fail — no guesswork, no multimeter needed
- Automatic 10-Cycle Test: Evaluates contact timing and consistency for reliable results
- CE Certified: Meets CE safety and quality standards
- Compact & Durable: ABS construction, lightweight at just 148g
- Three Relay Receptacles: Accommodates different relay footprints in one unit
Specifications
- Model: CNBJ-707
- Operating Voltage: 11V–15V (12V car battery)
- Ideal Coil Resistance: 20 ohms and above
- Material: ABS plastic
- Dimensions: 13 × 10 × 2 cm
- Weight: 148g
- Certification: CE
- Batteries Required: No (powered by car battery)
How to Use
- Connect the black alligator clip to the battery's negative terminal and the red alligator clip to the positive terminal.
- The tester powers up — RED LED illuminates to confirm power.
- Identify whether your relay is 4-pin or 5-pin and select accordingly on the tester.
- Plug the relay into one of the three receptacles on the tester.
- Press the TEST button.
- Wait for the result: GREEN LED = relay is functioning correctly; RED LED = relay has a fault or unrecognised pin layout.
- Disconnect the alligator clips and remove the relay when done.
Important Notes
- Use only with 12V car batteries within the 11V–15V voltage range.
- Best results with relay coil resistance of 20 ohms or above.
What's in the Box
- 1 × Universal 12V Automotive Relay Tester (CNBJ-707)
Looking for more automotive and diagnostic tools? Check out our Air Compressor Pressure Gauge and our Electromagnetic Induction Tester – Coil & Circuit Fault Detector for more professional-grade diagnostic solutions.
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Frequently Asked Questions
Q: What types of automotive relays can this relay tester check?
A: The Universal 12V Automotive Relay Tester is compatible with the most common 4-pin and 5-pin automotive relays. It features three relay receptacles to accommodate different relay footprints, making it suitable for a wide range of standard car relays used in most passenger vehicles.
Q: Does the automotive relay tester need its own batteries?
A: No — the tester is powered directly by your vehicle's 12V car battery via alligator clip leads. The battery voltage must be in the 11V–15V range for accurate testing. No separate batteries or power adapters are required.
Q: What do the green and red LED indicators mean on the relay tester?
A: A GREEN LED means the relay has passed all checks — pin configuration, contact closure/opening timing, and consistency across 10 test cycles. A RED LED indicates a fault: the relay's pin layout may not match standard configurations, the relay contacts may be damaged, or the timing test failed. Always replace a relay that triggers the red LED.