Q: Check Engine Light is on - code P0126

asked by on November 05, 2016

Check Engine light. Error code P0126. Called Mazda and was told thermostat needs to be replaced
My car has an automatic transmission.

Check Engine Light is on Inspection $94.99 - $114.99 Get a Quote

Hello there. Many common faults will cause the P0126 Code with your 2008 Mazda 3. The P0126 code meaning is "Insufficient Coolant Temperature for Stable Operation." This is telling us the car is reading a coolant temperature that is below specifications. Common faults that will cause this code are the coolant temperature sensor, thermostat, a wiring harness fault, or a failing temperature gauge.

A qualified technician, such as one from YourMechanic, can come to your location to determine why the Check Engine Light is on and suggest the needed repairs.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing


Experienced Mechanic?

Earn up to $70/hr

What others are asking

AC/heater not blowing on high.
Having your AC and Heater make a humming noise while running on high can be an annoying occurrence while you are trying to enjoy driving your truck. Since the problem is persisting after replacing the blower motor resistor, there are...
Antitheft system not allowing car to turn over
We must determine whether the fault concerns the vehicle or the lock and key set you carry personally. The vehicle system can have a faulty sensor or module causing your concern or a broken/weak transmitter in the key itself. Have...
Vibration coming from wheel and brake pedal when I'm idle
Hey there, thanks for writing in about your 2005 Scion xA. You need to check the brake booster to see if it has a vacuum leak (https://www.yourmechanic.com/article/is-it-safe-to-drive-with-a-vacuum-leak) in the check valve or booster when you are pressing on the brakes....
Warning lights come on while backing down a hill, Infiniti G25
There is a short somewhere causing the lights to work intermittently. However, to provide more insight as to where the short might be, I would need to know exactly which lights are illuminating intermittently. I'm guessing that it is not...
Car hesitates while accelerating, EGR valve is a recurring issue - 1999 Isuzu Amigo
Hello. If replacing the EGR valve (https://www.yourmechanic.com/services/exhaust-gas-recirculation-egr-valve-replacement) did not fix the issue, then the EGR valve was likely not the failed component. I would check to make sure that there are no exhaust leaks in the EGR system, as any...
Misfire after installing AC
Hello. In most cases the AC system should not affect the operation of the engine. If the issues only began after the AC was installed, it may be possible that the issue developed while the AC was being worked on....
Ac off due to high engine temp 2013 Chevrolet Malibu
Hello - there are actually 2 temperature sensors on your engine - the first reports temperature to engine management, which varies fuel mixture based on this and other variables. The 2nd temperature sensor feeds the temperature gauge in the instrument...
My van is a mazda mpv 2003. Our van was overheating. So we pulled over and all our water from the radiator leaked out.
You need to check the right rear under vehicle to see if your rear a/c heater hose is leaking or broke the control valve. If you did not break a hose you can bypass heater core by connecting the two...
When making left turns engine seems to make scratchy noiseg
The noise may be coming from the brakes or the rotor is hitting the backing plate for the brakes due to a loose wheel bearing. You should have the brakes and bearings checked.

Related articles

Symptoms of a Bad or Failing Air Pump
Common signs include the engine running rough, reduced horsepower, and the Check Engine Light going on.
P2289 OBD-II Trouble Code: Injector Control Press Too High-Engine Off
P2289 P2289 code definition Injector Control Press Too High-Engine Off What the P2289 code means P2289 is an OBD-II code for the engine control module (ECM) detecting the injector control pressure (ICP) sensor is registering a fuel pressure that is...
P0781 OBD-II Trouble Code: 1-2 Shift Malfunction
P0781 code mean there is an detected problem within the 1-2 shift function often due too internal blockages or failed transmission parts.