- Pre-heating is started in phase 1 as soon as the ignition turns on. Glow plugs heat up to 1300 degrees Celsius quite quickly.
- Phase 2: Heating to ensure effective fuel combustion during beginning.
- Third phase: post-heating After the engine has started, BERU glow plugs continue to heat for around three minutes. As the combustion chambers heat up, the prolonged glow plug working period aids in completing the combustion process and reducing noise production.
The BERU glow plug control unit also provides additional diagnostic information when the engine is not operating as it should.
In particular during cold weather, advanced BERU technology increases the efficiency of the ignition process, substantially reducing start-up times.
In This Article...
The three main types of BERU glow plug control units are:
The glow plug control relay regulates and modifies the current given to the glow plugs by comparing data from sensors to values computed by the control unit.
The ECU sends requests for glow function to the glow plug control unit with Application Specific Integrated Circuit (ASIC). It is perfect for low-voltage glow plug flow control and monitoring. It offers improved voltage adaption, voltage management, and streamlined diagnostics.
Through a BUS-system, the microcontroller communicates with the ECU in both directions. The control unit is able to accurately manage and change the necessary voltage since data is provided through the unit to the glow plug while feedback is also sent back to the ECU at the same time. Full diagnostics and an error memory are also included in the device. The glow plug features an emergency function to ensure engine startup in the event of a BUS network failure.
What is a glow plug relay?
The glow plug control device turns on and off the current for the glow plugs using a glow plug relay. The circuit will require more current the more glow plugs being watched by a control device. Glow plugs are frequently split across two circuits using two glow plug relays in order to reduce the amount of electricity required. Those older glow plug systems frequently employ this.
The ignition process of a diesel-powered car
Here is what occurs when you start a diesel-powered car to put this into practice:
- To start the car, turn the key in the ignition;
- To establish the timings, electric current, and duration needed by the glow plugs, the glow plug control unit analyzes information from the ECU;
- The glow plugs receive electric current, which makes them glow;
- Fuel is sprayed directly onto the hot glow plug tip while intake air is squeezed;
- As soon as the compressed air and injected fuel combine in the heated cylinder, combustion begins;
- To ensure optimal fuel combustion and low emissions, the glow plug control unit keeps the glow plugs on for a period after the engine begins.
Advantages of Beru glow plug technology
- Glow plug components are designed, tested, and manufactured by BERU to adhere to OE requirements and safety regulations. This means that even on the chilliest mornings, you can rely on BERU glow plug technology for reliable starts.
- For diesel vehicles, BERU provides the broadest selection of glow plug control units, including the ideal model for your vehicle.
- And BERU doesn’t stop there; it keeps making investments in new items to satisfy consumer demand.
Original Equipment (OE) manufacturer standards
Internationally recognized for providing cutting-edge ignition systems that satisfy OE manufacturer standards is BorgWarner, the manufacturer of BERU devices. Glow plugs made by BorgWarner are sold in the aftermarket under the BERU brand by Federal-Mogul Motorparts.
95 percent of the glow plug market for diesel automobiles in Europe is covered by BERU’s rapidly expanding lineup of glow plugs, and 90 percent of the glow plug control unit market is served by European vehicles with glow plug control units.
Are you interested in learning more about BERU glow plug technology? Read our article on glow plugs or our booklet on the technology behind glow plugs:
How can I tell whether my glow plug relay is operating properly?
Glow plugs can be tested using a digital multimeter (DMM), but it takes a little longer and is less accurate than clamp-meter testing. The most typical glow plug DMM tests are:
- examining the electrical resistance of the glow plug.
- Glow plug power supply inspection (electrical voltage).
Check your multimeter’s specifications to see if it can measure low enough to provide an accurate reading before attempting to test the electrical resistance of a glow plug. Resistance for glow plugs typically ranges from 1 to 6. Use the “continuity” function of your multimeter if it can detect resistances that low to determine whether the glow plug is entirely damaged.
Testing glow plug resistance:
- The glow plug’s power cable should be disconnected. If you don’t do this, you’ll measure all the glow plugs’ resistance at once rather than just the one you want to test.
- Start the multimeter and choose “mode” or “resistance.”
- Connect one test lead from a multimeter to the engine’s ground (preferably near the glow plug).
- The (power supply) terminal on the top of the glow plug should receive the other lead.
- Look at the multimeter’s display to see the outcome. Keep in mind that a resistance of less than 6 typically denotes a “excellent” glow plug.
- Disconnect the glow plugs.
- Remove the test lead from the glow plug power source.
- Reattach the power cord to the glow plug.
- For each glow plug on an engine, repeat steps 59 once more.
Testing glow plug power supply:
Learn what voltage your glow plug operates at. The quickest approach to do this is to check up the component number on the manufacturer’s website using the plug’s part number. While some glow plugs use alternative voltages, most need 12V.
- Ensure that the engine is cold.
- Select “DC voltage” mode on the multimeter and turn it on.
- Look at the multimeter’s display to see the outcome.
- Eliminate the glow plugs.
- Remove the test lead that is attached to the engine ground.
The glow plug module’s function is what.
Glow plugs are heating elements found in each cylinder of a diesel engine that aid in the engine’s starting, as you are already aware. But how are your glow plugs’ general operations tracked and managed? Glow plug control module does this.
The control module, which is attached to the engine and directly connected to the engine control unit, employs a microprocessor to analyze data coming in from the engine control unit to ascertain details about the operation of the glow plugs. The timing and amount of current needed for the glow plugs, which will vary based on the engine’s starting temperature, are covered in here. During pre-heating to warm up the engine, stand-by time when the engine should be started, and post-heating to meet ever-stricter exhaust gas requirements and optimize combustion processes, the current to the glow plugs is turned on.
When you start up a diesel-powered vehicle, the following actions happen:
- Using information from the Engine Control Unit, the Glow Plug Control Module calculates the timing and electric current needed by the Glow Plugs;
- The glow plug’s heating element is electrified, which causes it to heat up and generate visible light (thus the name);
- compressed intake air;
- Fuel is sprayed by the fuel injector onto the glow plug’s hot tip;
- Even when the engine is cold, the injected gasoline mixes with the compressed air, evaporation begins, and combustion begins practically instantly;
- To ensure proper fuel combustion and lessen the impact of your car on the environment, the glow plug is left on during the pre-heating phase of the engine.
The compression-induced rise in intake air temperature and the comparatively low ignition temperature of diesel fuel aid in this process. The compression temperature may not be high enough to assure effective ignition of the injected gasoline in a cold diesel engine without a glow plug control module, thus one is still necessary. Increased exhaust emissions would be the outcome of this.
How much are glow plug replacements?
You should be aware that glow plug replacements are inexpensive if you put off changing your glow plugs due to the price. You may get a replacement glow plug for anywhere between $25 and $50, depending on the brand and quality.
If you have the necessary tools, changing the plugs yourself will save you money on labor. You can pay a mechanic labor fee of $90 to $200 to replace your glow plugs if you want to put convenience over quality.
The process could take up to two hours, depending on the layout of your engine and the mechanic’s level of experience. The more labor expenditures you incur, the longer the job will take.
Why do glow plug relays malfunction?
The glow plug relay is susceptible to natural wear and tear over time, like most other auto parts. Extreme heat exposure, varying electrical currents, and malfunctioning injectors can all contribute to speeding up the process.
Maintaining regular maintenance and getting your Mercedes serviced as soon as you detect any performance changes will help you get the most life out of it.
Can glow plugs prevent a car from starting?
You must have your car serviced if the diesel glow plugs aren’t working in your vehicle. There are a number of indications that your glow plugs may be defective or malfunctioning. You must pay close attention to how your automobile sounds and behaves so you can identify any issues early and schedule timely maintenance. If you don’t take care of the problem right away, it can worsen and you might end up stuck on the side of the road.
What signs or symptoms point to a failed glow plug?
Although DENSO glow plugs have a lengthy lifespan, wear and tear causes them to gradually deteriorate. How do you determine whether a set of glow plugs needs to be replaced? In this article, we examine six typical symptoms that suggest glow plugs may be defective or broken.
The dashboard’s engine warning light is frequently the first indicator that something is wrong. Vehicles with this light on should be taken as soon as possible to an authorized workshop for an accurate diagnosis and service. The engine warning light might appear due to a variety of defects; below, we list the indicators that suggest malfunctioning glow plugs.
1. Difficult start
The most typical sign of damaged glow plugs is an engine that is difficult to start. Without properly working glow plugs, the combustion chamber may not warm up to the proper temperature in cold weather to ignite the gasoline and start the engine. Glow plugs should be examined whether the battery or fuel are both in good condition.
2. An unreliable engine
Diesel engine combustion demands a high rate of compression as well as the proper timing and volume of fuel injection. This causes combustion of the diesel fuel to start. Problems with fuel quality, compression, and fuel injection can result in misfires.
Compression pressure and glow plug heat are the sources of the combustion chamber’s heat. For ignition to occur, it needs to attain a temperature of at least 450 F/232 C. The engine chamber won’t heat up to the proper temperatures if the glow plugs are defective.
3. erratic idling
The engine will become increasingly difficult to start as temperatures drop, idle erratically, and emit white smoke from the exhaust for many minutes after it eventually starts if one or more glow plugs are burned out, carbon clogged, or broken. Check the fuel injection time if the tips of every glow plug are scorched.
4. A reduction in fuel efficiency
Fuel efficiency is typically determined by temperature and fuel, not glow plug performance. Glow plugs do, however, occasionally play a part.
Diesel may be mixed with particular additives during the cold months to reduce its freezing point according on the local climate. Most likely, the energy level of the blended gasoline will be lower, and it will offer less fuel efficiency. To guarantee that all of the injected gasoline is thoroughly burned, engine operating temperatures should be regulated. Glow plugs contribute to the combustion chamber’s additional heating.
The engine’s performance will be compromised if the necessary temperature cannot be reached because of malfunctioning glow plugs, and it will have to work harder to satisfy the demands of the road. The car’s fuel economy will suffer as a result.
If the car exhibits any of the other symptoms indicated here in addition to beginning to exhibit decreased fuel efficiency, it should be taken as soon as possible to an authorized workshop for an accurate diagnosis and treatment.
5. White vapor
When there is insufficient heat to burn the fuel, white smoke frequently results. Unburned fuel particles exit the exhaust as smoke and frequently emit a strong fuel odor. White smoke from the exhaust is typical in cold weather until the engine has warmed up.
White smoke can be produced when starting an engine by damaged glow plugs or a malfunctioning glow plug control module. Low engine cranking speed, low compression, and air in the fuel system are just a few of the additional potential reasons why there is too much white smoke. After the engine has warmed up, if white smoke is still present, the engine may have faulty injectors, delayed injection timing, or a worn injection pump.
6. Dark haze
An imbalance in the air-fuel ratiotoo much fuel and not enough aircauses black smoke. This indicates that either there is an excessive amount of fuel being added or not enough oxygen is being supplied to burn the fuel. Glow plug malfunctions could interfere with the delicate diesel combustion process, which could cause the engine to exhaust black smoke. This is a red flag that something is awry, possibly with the glow plugs or other crucial combustion process elements.
Long recognized as a pioneer in OEM automobile technology, DENSO. As the leading manufacturer of automotive components today, we continuously spend in R&D to assist the top automakers in developing cars that are more responsive, efficient, and reliable.
A OEM-quality glow plug program for all manufacturers is offered by DENSO Aftermarket. DENSO Glow Plugs give customers a full range of options, from exceptional start-up performance to prolonged post-heating temperatures. All contemporary glow plug technologies, including single coil, double coil, extended post-heating, ceramic, and immediate heating, are covered by the program.