Has the radio in your GMC Sierra stopped working? If so, there are three common causes for this issue. They are a blown fuse, loose or corroded wiring, and a problem with the radio itself.
If your radio comes on but isn’t working, this article will cover that too: Please jump to the section that’s applicable to your truck.
Table of Contents:
The most common reason for a radio to stop working in a car is a blown fuse.
Radio Won’t Work At All Causes
This section covers a GMC Sierra’s radio would show no signs of life. If your radio is lighting up, but no sound is coming from the speakers, head down to the next section.
Cause 1: Blown Fuse
Always start with the simplest and easiest potential cause first, which is the radio fuse. You’ll need to check the fuse box to see if the radio fuse is blown.
How to Test a Fuse
Step 1: You’ll need to your GMC Sierra’s fuse box location. On most makes and models, it’s to the left of the driver’s seat (when you are behind the steering wheel).
Step 2: Once you access your truck’s fuse box, you’ll need to locate the radio fuse. You should see a schematic printed on the door.
Step 3: Test the fuse. There are two ways to do this. First, you can visually inspect your Sierra’s radio fuse. There’s a wire between the two prongs. If the connecting filament is damaged, power can’t reach the head unit, and the fuse needs to be replaced.
A better way to verify a fuse is functioning is to use a test light. This can be accomplished without even pulling a fuse. Here’s how:
Start by finding a good ground source on your Sierra to ground the test light to. You can usually find one inside the door jam that will reach the fuse box.
Next, turn the key to the accessory position, and touch the test light tip to both prongs.
If it only lights up for one prong, the fuse has failed, and you’ll need to replace it. If both sides light up, the fuse is fine.
Cause 2: Wiring Issue
If your Sierra’s radio fuse checks out, it’s time to determine if there’s a problem with the wiring harness going to the radio system.
Verify that your truck’s radio has a solid ground connection. Use a multimeter to verify the voltage level is accurate. Any issue with the wiring harness will prevent power from getting to the radio system and cause the fuse to blow again.
Cause 3: The Radio Itself
If there’s power going to your Sierra’s radio, and you’ve verified that the ground connection is good and it has power, the only way to get your car working is to repair or replace it.
The Radio is On But No Sound
Cause 1: Broken Antenna
When the tuner is on, there will be static. The CD player or Aux input should still work fine.
A broken antenna is one of the most common issues that cause your Sierra’s radio to stop working. Antennas are reliable, but they can weaken and eventually break entirely over time, mainly if you frequently utilize drive-through car washes.
If you suspect this might be the problem, check to see if your truck’s antenna is in good working condition (is it bolted on?). If it isn’t, then you should replace it.
Cause 2: Anti-Theft Mode
If your truck’s stereo is coming on and says to “input radio code, ” you’ll need to find. Most vehicles come with a card where the number is recorded or written inside the glove box on a sticker. Sometimes it’s printed on the back of the owner’s manual.
Some manufacturers will let you look it up online if you need the code. If that doesn’t work, you can take it to the dealer and have them pull it. Here are all the ways you can look up your Sierra’s radio code.
Cause 3: CD Player or Aux Button Has Been Touched
If your Sierra has a CD player or aux button and it was recently touched, then your radio may be stuck in that mode.
You can test this by attempting to connect another device, such as an iPod, to the car’s audio system. If it works, then there is likely an issue with the radio itself.
In this case, you should take your Sierra to a professional for repair or replacement.
Does the radio stop working when you crash?
No, your GMC Sierra’s radio should not stop working when you are in a car accident. If it does, then there may be an issue with the wiring or the radio itself (wiring short, blown fuse, no power, and ground connection).
You can check to see if any of the fuses in your vehicle have blown, and if they haven’t, then you should look for loose or corroded wiring in your electrical system.
One of my GMC Sierra’s speakers isn’t working.
The speaker could be blown. But, you’d likely hear a static sound from the speaker. It’s more likely to be caused by a damaged speaker wire.
If one of your Sierra’s door speakers isn’t working, the most common location of the short will be where the harness enters the door (since it moves).