A diesel engine requires a higher temperature in the combustion chamber to start than a gasoline engine. This is where the glow plug relay comes in: it controls the glow plug system and ensures that the glow plugs are heated briefly before the starting process. But what if the glow plug relay is defective? How can you identify and fix problems?
The Function of the Glow Plug Relay in a Diesel Engine
The glow plug relay is an important component in a diesel engine. It acts like a switch that closes the electrical circuit for the glow plugs, thus activating the glow plug process. This process is crucial for a smooth cold start, especially at low temperatures.
Imagine: It’s a freezing winter morning and your diesel vehicle won’t start. A common problem in this case: a defective glow plug relay.
Testing a diesel glow plug relay
Common Symptoms of a Defective Glow Plug Relay
A defective glow plug relay can manifest itself through various symptoms. These include:
- Starting difficulties: The engine is difficult or impossible to start when cold.
- Slow preheating: The glow plug light on the dashboard stays on longer than usual or doesn’t light up at all.
- Jerking during startup: The engine starts rough and jerks until it is warm.
- Unusual noises: Clicking or buzzing noises can be heard during the preheating process.
How to Test a Glow Plug Relay: Step-by-Step Guide
With a little manual skill, you can check the glow plug relay yourself.
Required Materials:
- Multimeter
- Protective gloves
Here’s how to proceed:
- Safety Precautions: Ensure the ignition is off and the engine is cold.
- Locate the Glow Plug Relay: The glow plug relay is located in the engine bay and is usually installed near the battery.
- Disconnect the Plug: Disconnect the plug from the glow plug relay.
- Connect the Multimeter: Set the multimeter to resistance measurement (Ohm) and connect the probes to the corresponding contacts on the relay.
- Measure Resistance: A functional relay should have low resistance (a few Ohms). High resistance or no continuity indicates a defect.
Measuring resistance with a multimeter
What to Do if Your Glow Plug Relay is Defective
If you have found a defect in the glow plug relay, it should be replaced. We recommend having the replacement carried out by a professional workshop.
Frequently Asked Questions About Glow Plug Relays
- How long does a glow plug relay last? The lifespan of a glow plug relay depends on various factors, such as the frequency of cold starts and the quality of the component. However, a glow plug relay typically lasts several years.
- Can I continue driving with a defective glow plug relay? It is difficult to start the engine with a defective glow plug relay, especially in cold temperatures. In the long run, a defective relay can also lead to damage to the battery and the starter.
- Where can I find the right glow plug relay for my vehicle? You can find the correct glow plug relay for your vehicle at a specialist retailer or online. When buying, pay attention to the manufacturer part number and compatibility with your vehicle model.
Need Further Assistance?
Do you still have questions about glow plug relays or need help with repairing your vehicle? Our experts at autorepairaid.com are always ready to assist you with advice and support.
Feel free to contact us via our website or visit our blog for more helpful tips and tricks about car repair.
