Key Warning Light (Red)

What does the red key warning light do and why is it on?

The red key warning light means there is a security error code. This light illuminates when the vehicle control modules see the ignition turned with a key that is not programmed to the vehicle or when there is an error within the security protocol of the vehicle’s security system.

Common reasons for this to happen

  • Faulty key
  • Dead key fob battery
  • Faulty key antennae
  • Faulty control module
  • Electrical interference

Can I drive with the red key warning light on? (Can I drive in Fail-Safe Mode?)

In most cases, the vehicle will not start when the red key warning light is illuminated. It will have to be towed to a repair facility capable of programming and servicing the security system of your specific vehicle.

How do I fix a red key warning light?

  1. Replace the key fob battery 
  2. If the concern persists, you will have to tow the vehicle to a repair facility capable of servicing your vehicle’s security system.
  3. Another option is to have a mobile key programmer to come to you and service the vehicle.

Frequently Asked Questions

What causes the red key warning light to come on?

  • In some cases, this can be caused by aftermarket keys being programmed to the vehicle. They don’t always retain the memory the way a dealership key will. 

My car wouldn’t start and the red key warning light was on but now it does, what’s wrong?

  • In some cases, if there is a loose connection in the system it can cause an intermittent failure. Check the physical appearance of your keys. If the keys show signs of damage or wear they may need to be replaced.

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Comments 6

Tom DeSiena

April 24, 2020

You are talking about the red circle where you put the key in ????


November 5, 2020

My car has the red key on, but when I start it it starts whaat would be the problem

Fred Yzquierdo

April 24, 2020

This is good information,I haven’t had any issues with this red light but in case I do I’ll know thank you so much.

Rodney Ursin

April 24, 2020

Thanx for the heads up!


April 24, 2020

I have “on occasion” left my key in the car and locked myself out. But, I have an unprogrammed key in my wallet just to get the door open. Most often the programmed key is still in the ignition. Can I safely assume that, using the programmed key, the car will start with no red light key showing?

John Setzke

April 24, 2020

I have had “FIXED” for several years and installed in my 2001 Dodge Dakota. When the truck started to run very rough if at all FIXED diagnosed my problem as being misfiring in 3 cylinders. This led to getting a repair bid of rebuilding the engine at the cost of $7000. I still have that truck trying to make a decision to either have a rebuilt engine installed or have the existing engine rebuilt or get rid of the truck.
Since then I have purchased a 2019 Toyota Highlander Hybrid.. My question is will the FIXED work in the new vehicle with all bells and whistles and the Hybrid system

Andrew Taylor

April 24, 2020

In most cases you can reset your own security system. I wrote this for the help website FIXYA where I often recommend FIXD.

This is how you reset an anti theft system if you have the anti-theft light on, or your car is cranking, but you have no spark.

Doing a full reset of the anti-theft system.

Disconnect both battery leads for at least two hours.
Hold the negative and positive leads together for 5 minutes to fully discharge any power.
Put the key in the ignition, but not turned on. VERY IMPORTANT!
Connect the positive lead.
Connect the negative lead in one swift movement.
Wait 15 minutes for the system to fully reset.

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