A Quick Overview
|Identify the Pins: Before you start, identify the pins on the 5-pin relay. These usually include two power pins (85 and 86), a common pin (30), normally closed (NC, 87a), and normally open (NO, 87) pins. Refer to the relay’s datasheet to confirm pin identities.
|Set Up the Multimeter: Set your multimeter to the resistance measurement mode, usually symbolized by the Greek letter Omega (Ω).
|Check the Coil Resistance: Place the multimeter probes on pins 85 and 86. This measures the coil’s resistance. The reading should be within the range specified on the relay’s datasheet. If it isn’t, the relay might be faulty.
|Check NC and Common Contact: Next, measure the resistance between the common pin (30) and the NC pin (87a). It should read close to zero ohms, indicating a closed circuit. If not, the relay may be faulty.
|Check NO and Common Contact: Measure the resistance between the common pin (30) and the NO pin (87). Your multimeter should read infinite resistance or “OL” (open loop), indicating an open circuit.
|Apply Power to the Coil: Connect a battery to pins 85 and 86 to energize the coil. Be sure the battery voltage matches the relay’s rated coil voltage.
|Re-check NO and Common Contact: While the coil is energized, measure the resistance between the common pin (30) and the NO pin (87) again. The resistance should now be close to zero, indicating a closed circuit.
|Final Determination: If the relay passed all these tests, it is likely in good working condition. If it failed any of these tests, it’s typically best to replace it.
Before we begin the testing process, here are some materials you’ll need:
- 5-pin relay
- Wire stripper/cutter
- Electrical tape
Steps to Test a 5-Pin Relay with a Multimeter
Follow these steps to test a 5-pin relay with a multimeter:
- Understand the Pin Layout
Before testing a 5-pin relay, it’s important to understand its pin layout. The pins are usually labelled as 85, 86, 87, 87a, and 30. The 85 and 86 pins control the switch inside the relay, while the 87 and 87a pins are the normally open and normally closed contacts, respectively. The 30 pin is the common contact.
- Set the Multimeter to Ohms
Turn your multimeter on and set it to the ohms setting. Depending on the type of multimeter, this may be labelled as Ω or resistance.
- Measure the Resistance of the Coil
Connect the multimeter probes to the 85 and 86 pins of the relay. The reading should be between 50 and 100 ohms. If the reading is out of range, the relay’s coil may be faulty and will need to be replaced.
- Test the Switch
Connect the multimeter probes to the 30 and 87 pins of the relay. The reading should be infinite or open circuit. If this is not the case, the switch inside the relay may be stuck closed, and the relay will need to be replaced.
- Test the Normally Closed Contact
Connect the multimeter probes to the 87a and 30 pins of the relay. The reading should be zero or short circuit. If this is not the case, the normally closed contact inside the relay may be disconnected, and the relay will need to be replaced.
- Test the Normally Open Contact
Connect the multimeter probes to the 87 and 30 pins of the relay. The reading should be infinite or open circuit. If this is not the case, the normally open contact inside the relay may be disconnected, and the relay will need to be replaced.
What is a 5-pin relay, and why do I need to test it with a multimeter?
A 5-pin relay is an electrical component used in automotive and industrial applications. It helps control the flow of electricity to various systems and components. Testing the relay with a multimeter can help you diagnose problems with the electrical system and ensure that the relay is working correctly.
What tools do I need to test a 5-pin relay with a multimeter?
To test a 5-pin relay with a multimeter, you’ll need a digital multimeter, a set of alligator clips, and a power source.
How do I test a 5-pin relay with a multimeter?
To test a 5-pin relay with a multimeter, you’ll need to follow a series of steps, including checking for continuity, testing the resistance of the coil, and testing the voltage of the switch. A detailed step-by-step guide can be found online or in automotive repair manuals.
What are the symptoms of a bad 5-pin relay?
Some common symptoms of a bad 5-pin relay include a failing or malfunctioning electrical system, an engine that won’t start or has difficulty starting, and issues with the lights or other electrical components.
How can I tell if my 5-pin relay needs to be replaced?
If you’ve tested your 5-pin relay with a multimeter and determined that it’s faulty, it will need to be replaced. Additionally, if you’re experiencing any of the symptoms mentioned above, it’s a good idea to have the relay checked and replaced if necessary.
Can I replace a 5-pin relay myself?
Yes, replacing a 5-pin relay is a straightforward process that can be done with basic tools and some knowledge of electrical systems. However, if you’re not comfortable working with electrical components, it’s always best to have a professional mechanic handle the job.
Where can I find a replacement 5-pin relay?
Replacement 5-pin relays can be found at most automotive parts stores, as well as online retailers. Be sure to get the correct model for your specific vehicle or application.
How much does it cost to replace a 5-pin relay?
The cost of replacing a 5-pin relay varies depending on the make and model of your car and the location of the relay. On average, you can expect to pay between $20 and $50 for the part and labor. However, prices may be higher for certain vehicles or more complex repairs.