Glow Plug Light Flashing VW

Volkswagen is a brand that’s known for its rich offer of models, all of which boast reliability. However, even with the reliability of Volkswagen, problems can appear. One of these is glow plugs. The warning light is a great way to know if something is up so let’s see how it works in a glow plug light flashing VW.

Glow plugs


A glow plug is a component within the car that acts as a small heater. The vehicle will have multiple of these heating elements, which can be found in the car’s bonnet.

Their job is to heat up the air and diesel in the engine in order to enhance combustion.

This means they share a similar purpose as spark plugs. However, spark plugs are specifically for sparking the ignition, hence their name, while glow plugs simply ready the mix for the eventual ignition.

Glow plugs are especially useful for starting the car in cold weather. They keep the fuel at a decent temperature that allows spark plugs to do their job properly.

A car will have one glow plug for each vehicle it has. Four-cylinder cars get four glow plugs, six-cylinder ones six, and so on.

However, your glow plugs can malfunction. When they do, glow plugs will quickly stop to function completely.

Thankfully, the glow plug warning light exists to tell us when a problem with such a component is imminent. With the aid of this warning light and some knowledge, we can stop the issues early.

This can save a lot of time and money car owners would otherwise spend resolving glow plug problems.

Glow Plug Light Flashing VW


The glow plug light flashing is a signifier of other problems. Complex pieces of machinery that they are, vehicles are made in a way where many symptoms will crop up before a considerable problem affects the car. 

With the glow plug light flashing on Volkswagen cars, we get a heads-up on problems that could cause considerably more damage.

Common Problems That Cause Glow Plug Light Flashing VW Brand


Even among all the possible problems, there will always be some which are more common than others. These problems are the ones most worth looking out for.

Their symptoms are more likely to appear and the problems they bring are more immediate.

  1. Failed glow plugs

A very simple explanation for your glow plug light flashing could be that they got worn out. When this happens, a glow plug will cease to function, failing to do its job.

No matter whether our vehicle has one or multiple glow plugs failing, the glow plug light will start flashing to alert the owner of the vehicle. [1]

It bears mentioning that glow plugs usually last for 100,000 miles. Volkswagen being a reliable manufacturer means that this distance should be consistently reached by cars from their production lines.

However, if the glow plug fails early in its lifespan we may have a different concern to take care of.

  1.  Glow plug relay malfunction

If it’s not the glow plugs themselves, then the flashing could be caused by the glow plug relay. The glow plug relay itself is used to switch the current for the glow plugs on and off.

Generally, the more glow plugs there are the higher current is required and the better glow plug relay for managing them. However, no current will be properly managed if the relay malfunctions. [2]

  1. Control module

The control module within a car is meant to regulate several components within the car. Along with some of the key parts of the car’s functionality, this component also controls glow plugs. Its job in the matter is to properly maintain its function.

Control module malfunctioning will put our glow plugs out of commission which means the warning light will turn on to signal a problem occurring. The problem with the control module can often be resolved with the proper check at the mechanic’s shop. [3]

Though generally these problems will show also be premeditated by the malfunction of other car systems. These include ignition and exhaust ones, which should have their own symptoms that manifest.

  1. Damaged Wiring

Individual components and wiring wear out in the same manner. Usually because of time wearing them out. The problem this can cause is quite imminent.

However, it can also be a localized issue. One where the part of the wiring that ends up worn out can be replaced without any extra tweaks. [4]

If the wiring does get damaged glow plug is likely to stop working. The effects of this particular malfunction are imminent. The glow plug will simply not do its job.

A damaged piece of wiring cuts off the chance of the aforementioned component to transfer information through the car which immediately results in the glow plug failing as well.

The warning light is bound to flash as soon as the wiring gets to a point where it’s causing issues with the consistent work of the glow plug. That means early resolution is possible and desired.

By engaging with the particular issue, we can stop further problems that would come from other pieces of malfunctioning wiring.

Solutions to glow plug light flashing in Volkswagen


The problems laid out above can often be addressed. While a visit to the mechanics’ shop is a guaranteed way to diagnose and fix your car, it pays to do some of the work yourself.

A general slew of solutions requires only general tools along with potential replacement parts.

Replacing a glow plug ends up being a solution to the issues that mention them being the source of the problem. The glow plug could’ve gotten worn out or damaged. Getting a new one will result in our car being back in top shape.

Diagnostics are an important part of the problems such as control module malfunction. Utilizing a diagnostics tool correctly can help us learn the exact nature of the problem. One that we would have a much worse time resolving without proper information.

These tools are really easy to use, just plug them into the diagnostics port and read off the errors given. Reference the errors or look them up online to fully understand how they affect the vehicle. Once that’s done, the solution will come easily.

Our Volkswagen can be heavily hampered in its functions by malfunction of glow plugs. That’s why recognizing symptoms and applying the solutions is so important. No matter the degree of the problem, this immediate help is important.

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The problems of the Volkswagen glow plugs can be numerous but they aren’t too difficult to distinguish. The symptoms are apparent no matter the source of the issue.

No matter whether it’s a problem of a failing glow plug or control module, there are solutions to be had.

These solutions can be applied at home, which makes it far easier to resolve than certain other issues. Of course, should the issues become too prominent, a visit to the mechanic’s shop is recommended.

With an understanding of why your glow plugs light flashes, you can extend the lifespan of your Volkswagen by a considerable amount.

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