Automotive relay testing

Types of Automotive Relay Testing

Automotive relay testing is a crucial aspect of automotive electrical system maintenance and repair. It ensures the reliability of the automotive relay, which acts as a switch to control high-current circuits using low-current signals. Below are the different types of automotive relay tests.

• Visual Inspection

  Visual inspection is the first step in automotive relay testing. Technicians examine the relay and its surrounding wiring for any visible signs of wear, damage, or corrosion. They also check for burnt marks on the relay's casing, which may indicate that the relay has been faulty. Moreover, loose or damaged connections and broken or frayed wires are also looked out for, as they may affect the relay's performance.

• Click Test

  The click test is performed to check whether the relay is operating. The technician removes the relay from the vehicle and applies the rated coil voltage. If the relay is functioning normally, a clicking sound will be heard as the internal switch closes. On the other hand, if there is no sound or inconsistent noise, the relay may be faulty and require replacement.

• Current Draw Test

  This test is done to ensure that the relay's contacts are not too high and that the normal function of the circuit they control is not interrupted. A multimeter is used to check the current flowing through the contacts of the relay. If the current reading is above the specified limit, it indicates that the relay contacts are either too closed or too open, and the relay requires replacement.

• Voltage Drop Test

  Voltage drop tests are done to check the integrity of the relay contacts. A multimeter is used to measure the voltage across the contacts of the relay while it is energized. If the measured voltage is lower than the specified value, it indicates that the relay contacts are not making a good connection, which may cause circuit performance issues.

• Coil Resistance Test

  The coil resistance test is performed to check the condition of the relay coil. A multimeter is used to measure the resistance of the relay coil. The reading should be within the manufacturer's specified range. If the resistance is too high or too low, the relay coil may be damaged and need replacement.

• Functionality Test

  The functionality test is done to ensure that the relay operates according to the manufacturer's specifications. The relay is tested using a specialized automotive relay tester or a multimeter and power supply. The relay should switch the load circuit on and off in response to the control circuit signal. If the relay does not perform its switching function, it is faulty and needs to be replaced.

• Thermal Imaging

  Thermal imaging is used to detect any overheating relays. An automotive thermal imager scans the relay during operation. If the relay is abnormally hot compared to other relays or the specified temperature, it indicates that the relay is faulty.

Specification and maintenance of automotive relay testing

Automotive relay testing is a crucial aspect of automotive electronics. The specification and maintenance of automotive relay testing are essential to ensure the accuracy and reliability of the testing process.

Specification is the process of defining the requirements of a relay test. It includes the type of relay to be tested, the test parameters, and the test equipment required. The specification should be precise and accurate to ensure that the relay test is reliable and repeatable.

Maintenance is essential to ensure that the testing equipment used for relay tests is accurate and reliable. Regular calibration of the testing equipment is necessary to ensure that the measurement accuracy is maintained. The automotive relay tester should be kept clean and free from dust and moisture to ensure its reliability. The test equipment should be used and handled according to the manufacturer's instructions to ensure its reliability.

Specification and maintenance of automotive relay testing are essential to ensure the accuracy and reliability of the testing process. By following the specified requirements and maintaining the testing equipment, the reliability and repeatability of relay tests can be ensured, which is crucial for the normal operation of automotive electronics.

• 1. Use a relay tester according to the manufacturer's instructions, and keep it clean and dry to ensure accurate measurements.
• 2. Test the relay according to the specified test procedures, measure its parameters, and compare them with the manufacturer's specifications.
• 3. For abnormal conditions, use professional maintenance tools to disassemble and repair, or replace with new relays.

How to choose automotive relay testing

Here are some of the factors that are considered when testing automotive relay are as follows:

• Power Supply:

  Automotive relay testing requires a power supply that is sufficient and provides stable voltage. The power supply is used to energize the relay coil during the test.

• Load Testing:

  Load testing is done by connecting a load to the relay contacts. The load that is connected is the one the relay is designed to control. The load is used to test if the relay contacts are able to close.

• Control Circuit:

  The control circuit is used to energize and de-energize the relay coil. The control circuit can be a simple switch or a more complex circuit.

• Measuring Instruments:

  Measuring instruments are used to monitor the voltage and current during the tests. This includes multimeters and oscilloscopes.

• Troubleshooting Tools:

  Troubleshooting tools are used when testing indicates a failure. This includes tools like diagnostic scanners and automotive oscilloscopes.

• Safety Equipment:

  Safety equipment is used during automotive relay testing. This includes gloves, safety glasses, and insulated tools to protect the user from electrical hazards.

How to DIY and Replace Automotive Relay Testing

Before carrying out any DIY tests on automotive relay controls, ensure to have the right tools for the job. One will need a multimeter, relay tester, wiring diagrams for the specific vehicle, and possibly some basic hand tools like screwdrivers and pliers. It is also advisable to have a non-contact voltage tester for safety precautions.

Once the tools are in place, do the following:

• Identify the Relay: Using the vehicle's manual, identify the problematic circuit's relay.
• Inspect the Relay: Visually inspect the relay for any signs of damage, corrosion, or burning.
• Test the Relay with a Relay Tester: Connect the relay tester to the automotive relay and follow the manufacturer's instructions. This step will show if the relay is working and the level of its pull action.
• Test the Relay with a Multimeter: For more advanced tests, use a multimeter to check the relay's coil and contact resistance. The readings should be in line with the specifications in the manual.
• Check Control and Load Sides: Using wiring diagrams, check the control side for signal presence and the load side for continuity if the relay is activated.
• Replace the Relay if Necessary: If all other tests show that the relay is not functioning, replace it with a similar one.

Note: It is important to use a relay that is exactly like the one used in the previous case. Otherwise, the relay may not function properly or may damage the vehicle's circuitry.

Q and A

Q1: What is an automotive relay?

A1: A relay is a switch that allows a circuit to be opened or closed automatically or be controlled by a low-power signal. Relays are used in various applications, such as controlling lights, motors, and other accessories.

Q2: What is automotive relay testing?

A2: Automotive relay testing is checking and inspecting the relay to ensure it functions correctly. This involves measuring the relay's resistance, checking its voltage and current ratings, and inspecting its contacts and coils for wear or damage.

Q3: Why is automotive relay testing important?

A3: Testing is crucial because it helps identify potential relay failures that could cause system malfunctions. By ensuring that automotive relays are in good condition, vehicle owners can avoid unexpected breakdowns and maintain the reliability of their vehicles.

Q4: How often should automotive relays be tested?

A4: There is no specific frequency for testing automotive relays. However, it is recommended to test them periodically, especially in critical applications or when symptoms of relay failure are observed.

Q5: What are the common relay problems detected during testing?

A5: Relay problems include contact wear, coil failure, and signal switching errors. These issues can affect the performance of controlled circuits and require prompt relay replacement or repair.