What is a Multifunction Switch and What Does it Do?

Safety when turning is paramount. To ensure that, every car comes fitted with what’s called a multifunction switch. But with its many functions, what does the multifunction switch do? We compiled this guide to explain everything you need to know about this type of car switch including its functions, location, and other important details such as its repair and replacement.

What is a Multifunction Switch?

The multifunction switch is a mechanical switch that uses electrical signals to operate various car functions. When you move the lever, it activates a series of switches that send electrical signals to the corresponding car system.

For example, when you activate the turn signals, the multifunction switch completes an electrical circuit that powers the turn signal lights.

The multifunction switch is a stalk that protrudes from the steering column and controls various functions, but chiefly the turn signals. Because its primary function is to control the turn signals, it’s also commonly called the turn signal switch.

Other names that the multifunction switch goes by are the blinker switch, turn signal flasher switch, turn signal switch, combination switch, turn signal lever, and turn signal stalk.

As can be seen in the image above, the multifunction switch assembly is usually connected to a lever that can be turned up, down or sideways to operate various car functions -and why it’s called a multifunction switch.

There are two types of multifunction switches that you may find used in cars -the older mechanical type and the newer electronic type. The older type uses a thermal flasher unit to operate the turn signals, while the newer switch uses the car computer to do so.

Where is the Multifunction Switch Located?

A multifunction switch is typically located on the left side of the steering column and attached to the steering column using screws. In some cars however, the switch is integrated into the steering column and mounted just below the steering wheel.

With the convenient location of the multifunction switch, car drivers can comfortably and easily operate the turn signals without having to take their hands off the steering wheel. Let’s now have a look at the many different functions of the switch.

What Does a Multifunction Switch Control?

Or rather, what does a multifunction switch control? The multifunction switch has various functions, the most important of which is controlling the turn signals. But that’s not all this switch does. Modern cars have additional features that the multifunction switch also controls. These include

• The high beam headlights
• The fog lights
• The windshield wipers
• The horn

The multifunction turn signal switch is responsible for operating all these functions. In some cars, the switch may also control other features such as cruise control, headlight dimmer, and lane change signals.

How Does a Multifunction Switch Work?

Now that we’ve seen what the multifunction switch does, let’s take a look at how it works. To help you understand the switch’s operation, let’s first see the parts that make it. The typical multifunction switch assembly has the following components.

• The switching mechanism, including the canceling cams
• The switching lever/stalk
• The wiring system

The switching assembly is the heart of the multifunction turn signal switch. It’s a set of electromechanical switches that are activated when the multifunction lever is moved. These switches complete or break electrical circuits to operate various car functions.

The switching lever is what you see and use to operate the multifunction switch. The lever is connected to the switching assembly and moves it when operated.

The wiring system is a set of electrical wires and connectors that provide power to the switch and carry electrical signals from the switch to the car computer.

Bad Multifunction Switch Symptoms

Like any other part on your car, the multifunction switch can also have problems. These can range from worn-out parts to a loose connection. When the switch starts to fail, you’ll notice certain symptoms. The most common symptoms of a bad multifunction switch are listed below.

Turn Signals Not Working

This is one of the most common bad multifunction switch symptoms. If the turn signals are not working, it’s most likely because the switch is not sending a signal to the car’s computer. This could be due to a loose connection, a worn-out part, or another issue such as a blown fuse.

In most cases, this symptom means a multifunction switch that needs replacing. It’s crucial to test the switch first, though, since there could be other issues that are causing the turn signals to fail.

Turn Signals Work Intermittently

If the turn signals work sometimes but not all the time, it’s a sign that the switch is starting to fail. The problem may be with the switch itself or with the wiring system.

Intermittent turn signal problems are often caused by loose electrical connections. Check the wiring and connectors first to see if they’re loose or damaged. If they seem to be in good condition, replace the multifunction switch.

Turn Signals Not Canceling

Another symptom of a bad turn signal multifunction switch is that the turn signals do not cancel. In most cars, the turn signals are supposed to cancel themselves after you make a turn. If they don’t, it’s usually because there’s something wrong with the switch.

This problem is usually caused by a worn-out part in the switch, typically the canceling cam. Over time, the switch’s moving parts can wear out, causing the signal to stay on even when it’s not supposed to. Replacing the switch should fix this problem.

Switch Controlled Systems Do Not Work

As you already know, the multifunction switch is responsible for operating various car systems. So, if one of these systems suddenly stops working, the switch may be to blame.

For example, if your windshield wipers stop working, it’s possible that the switch is not sending a signal to the wiper motor. This could also be caused by a loose connection, a blown fuse, or a problem with the switch itself.

Other systems that can be affected by a bad multifunction switch include the headlight dimmer and the high beams. If any of these systems stop working, check the multifunction switch to see if it’s the cause.

How to Test the Multifunction Switch

Upon noticing the first multifunction switch symptoms, we advise that you quickly take action to find out the problem’s source. Failing to do so can result in more serious problems, and perhaps costly repairs. Here is how to test a multifunction switch using a multimeter.

• First, locate the multifunction switch. In most cars, it’s located on the steering column’s side, sometimes below the steering wheel.
• Once you’ve found it, remove the switch from the car.
• Next, use your multimeter to test the switch various terminals for continuity.
• Set your multimeter to the continuity setting and touch one probe to each of the switch’s terminals.
• If the meter beeps, it means that the switch is good. If there’s no continuity, the switch is bad and needs to be replaced.

Multifunction Switch Repair

With the multifunction switch not working, you cannot safely drive your car. The turn signals are a crucial part of driving, and without them, other drivers will not know what you’re planning to do. That’s why it’s important to fix the problem as soon as possible.

When you have a bad turn signal switch, you can either fix or replace it. Multifunction switch repair is your first option, especially if the switch is relatively new. Sometimes, the problem can be fixed with a simple adjustment or by cleaning the switch’s electrical contacts.

That said, here is how to repair multifunction switch assemblies in most cars:

Step 1 Disconnect the battery

• Before anything else, disconnect the battery to avoid accidents. Find the battery under the hood. It’s usually located near the front of the car.
• Remove the negative cable first. To do this, loosen the bolt that secures the cable to the negative terminal. Then, pull the cable off the terminal.

Step 2 Remove Multifunction Switch

• Once the battery is disconnected, remove the multifunction switch from the car. In most cars, the switch is located on the steering column side.
• You will need a screwdriver to take out the switch- and a panel or two.
• Start by removing the two screws that hold the switch in place.
• Then, pull the switch out of the steering column.

Step 3 Inspect Multifunction Switch

• If the switch is not working properly, the problem might be with the electrical contacts. Over time, these contacts can get dirty or corroded, which can prevent them from making a good connection.
• To clean the contacts, start by removing any dirt or debris that might be on them. Use a small brush or a can of compressed air to remove any dust.
• Then, use a wire brush to remove any corrosion from the contacts. You may also need to adjust or tighten any loose parts.

Step 4 Replace the Switch

• Re-install the switch. This process is the same as removing the switch but in reverse.
• Start by putting the switch back into the steering column. Then, secure it in place with the two screws.
• Finally, reconnect the battery.

Multifunction Switch Replacement

If the switch is old or damaged, it’s usually best to replace it. This is because multifunction switches are not designed to be repaired. Besides, replacing the switch is also a much faster process than trying to repair it. Here is how to replace a multifunction switch:

Step 1 Disconnect the Battery

As always, start by disconnecting the battery. To do this, find the battery under the hood of the car and loosen the bolt that secures the negative cable to the negative terminal. Then, pull the cable off the terminal.

Step 2 Remove the Old Multifunction Switch

With the battery disconnected, you can now remove the old switch from the car. The switch is located on the steering column. Start by taking out the two screws that hold the switch in place. Then, pull the switch out of the steering column.

Step 3 Install the New Switch

Now, you can install the new switch. This process is the same as removing the old switch but in reverse. Start by putting the new switch into the steering column. Then, secure it in place with the two screws. Reconnect the battery.

Assuming you have a basic understanding of car repairs, that should give you a good starting point on how to fix or replace a multifunction switch. As always, if you’re unsure of anything, it’s best to consult a professional, which brings us to the question: how much does it cost to replace a multifunction switch?

Multifunction Switch Replacement Cost

The cost to replace the multifunction switch will, first, depend on the make and model of your vehicle. For example, a Toyota Camry will have a different cost than a Ford Mustang. Second, multifunction switch replacement cost depends on whether you do it yourself or have someone else do it for you.

Doing it yourself will obviously be cheaper since you’re only paying for the cost of the switch and not labor. Expect to pay anywhere from $50 to $100 for the switch itself. If you’re having someone else do it, then the cost will obviously be higher. Expect an amount anywhere from $100 to $200 for labor and parts.

Conclusion

As its name suggests, the multifunction switch is a switch with multiple functions. As such, it’s crucial to ensure that the switch is in good working condition every time you sit behind the steering when to go out driving. We hope this article has helped you understand more about multifunction switches and how to fix them if they’re not working properly.