How to replace a turn signal switch
Turn signal switches have become complicated over the years. What was once just a lever to activate the turn signals has added more functions: Headlight dimmers, flashing lights and even the horn button. Other stalks have also sprouted from the steering column, including wiper controls and cruise control. Each addition has made changing the turn signal switch just a little more complicated.
If the turn signal switch fails, it will probably be difficult to use it at first. Seems to be loose or stops when you finish a turn. The turn signals could stop working, or the headlight dimming function becomes intermittent.
When turn signals stop working, you need to troubleshoot before you start replacing expensive parts. If the switch is flying around in your hand, it needs to be replaced, but other problems can occur elsewhere in the system.
- ½ inch drive break bar
- Marker pen
- Safety glasses
- Screwdriver, Phillips head and flat head
- Socket set: ½-inch drive and ¼-inch drive
- Steering wheel puller
- Torx bits
- Workshop manual
Part 1 of 3: Remove the steering wheel
Step 1: Disconnect the battery. If your radio has an anti-theft security code, make sure you know what it is before proceeding. Put on your safety glasses, then loosen the battery cable clamp (usually a 10-13 mm nut) and pull off the cable.
This is necessary to prevent an airbag code from being set when the steering wheel is removed.
Step 2: Remove the driver's side airbag. Most cars have Torx fasteners that hold the airbag to the steering wheel, accessible from the side of the steering wheel facing the dashboard.
Usually you can simply unscrew these fasteners, pull off the airbag insert and disconnect a small electrical connector at the back of the airbag.
- Warning: airbags can be dangerous! Consult your workshop manual for the proper procedure to remove the air bag. Some models require you to perform a deactivation sequence, while others are no more complicated than removing a horn button. Whatever it is, be sure to follow all safety instructions for removing and handling the airbag.
Step 3: Remove the steering wheel. Remove the nut or bolt in the middle of the steering wheel. Place the steering wheel straight ahead. Mark the steering wheel and shaft with a marker pen so you can put the wheel back exactly as it came out. Then try to wiggle it off.
Sometimes a few raps with the heel of the hand is all that is needed. In other cases, you will need to install a steering wheel puller to generate enough force to remove it.
If it comes loose, carefully pull it off the shaft while watching for electrical connections that need to go through the steering wheel.
Step 4: Remove the steering column cover. How much of the trim needs to be removed varies from car to car, but the lower half of the steering column trim almost always needs to come out.
Removing the steering wheel may have exposed some bolts, or all bolts may be accessible from the bottom of the column. Trace the screws and the positions they were in.
Step 5: Remove the clock spring. The next part you will encounter is the clock spring. It is a plastic housing with warning labels.
It contains a band of wire that is wound up like a loose spring and allows the steering wheel to fully lock right and left and still maintain a tight connection with the airbag controller.
The clock spring can be bolted to the steering column or it can simply snap into place. It attaches to the steering column so that it turns with the steering column. The electrical connector to the car is usually located under the center of the column. All connectors in the airbag electrical harness are yellow or orange to distinguish them from other systems in the car.
Disconnect the harness connector and pull the clock spring off immediately. Place it somewhere where it will not be disturbed. You don't want the center of the clock spring to turn while it is off the steering column. Some cars have a hole in the clock spring for inserting a pin to prevent it from moving while it is out of the car.
Part 2 of 3: Replace the turn signal switch
Step 1: Remove the turn signal switch. The turn signal switch can be held around the column with a few screws or a clamping screw.
It could be a massive multifunction switch arrangement, or the various switches could be discrete little boxes that move away from each other separately.
The column switch could be disconnected on the right rear, or there could be a wiring harness that extends across the column. Look at the back of the switch to see what the arrangement is. There should be enough slack so you can pull it back a bit and leave it hanging.
Step 2: Disconnect the wiring harness. Sometimes the wiring harness connector is located in the steering wheel fairing. On some cars, you may find that the harness goes all the way over the pillar into the dashboard. If this is the case, you will need to remove the lower covers under the dashboard to access the connectors.
At this point the harness may just fall out of the bottom of the column, or you may have to pull it out and pull it through an opening. Pay close attention to the location of the harness and how well it is secured. Many cars with tilt steering columns allow the wires some movement, and you don't want them caught on anything.
Step 3: Install the new switch. Put the switch back in the column and reinstall the screws. Install any other switches you may have had to remove as well.
- Note: If there are hidden fasteners on the steering wheel fairing, you must reattach the fairing before the next use.
Part 3 of 3: Reattach the steering wheel
Step 1: Reinstall the clock spring. The clockspring should not have been disturbed while you had it off, so you can just slide it straight down onto the shaft, making sure that the flats on the shaft properly engage the center of the part.
- Note: If you had a needle in the watch spring, take it out.
Step 2: Reattach the steering wheel. Align the match marks you made on the steering wheel and shaft, and reattach the steering wheel to the spline, passing the airbag wire through the appropriate holes at the same time. Install the bolt and tighten it with a torque wrench.
- Note: The workshop manual should have the factory specification.
Step 3: Install the airbag. Put the airbag back in the way it came out. Be sure to connect the small two wire connector on the back side.
If there was a deactivation procedure, reactivate the airbag by reversing the procedure according to the workshop manual.
Step 4: Test the turn signal switch. Start the car and try all the switches: turn signals, headlight dimmer, windshield wiper and horn. Take the car for a test drive and check cruise control.
Note if there is an airbag warning light on the dashboard. If you disconnected the battery before starting the job and only reconnected it when the airbag was plugged in, this should not be a problem. An airbag code is displayed if at any time you had the key turned on while the airbag was disconnected, and it can only be reset with the appropriate scanner.
The turn signal switch can be a handful because everything in the steering column is packed very tightly. There is also the added complication of dealing with the airbag system. If you're worried about working with the airbag or clock spring, or the steering wheel isn't aligned properly, Vermin-Club can send a technician to your home or office to service your turn signal switch.