check engine light scan

Why is my check engine light on ?

The history of check engine light

In 1968, the first automotive computer was released on a Type 3 Volkswagen. This computer system did not have diagnostic capabilities for a technician. 

In 1975, the first car computer was able to produce check engine lights. This computer program was in the Datsun 280Z and Cadillac Seville cars. The operating system was made by Bosch and Bendix. 


OBD stands for “On board diagnosis”. In 1980, GM released its first version of the modern check engine light. OBD0 on the 1980 Eldorado. The OBD0 light was often called an idiot light. 

GM introduced an electronic carburetor in 1981. They had two and four-barrel versions. The carburetors were able to change the air-to-fuel mixture ratio. 

How do you pull the obd0 codes?

To pull a Honda CRX OBD0 code, first, you need to have your car turned on. Then, you connect the “jumping wire” to the blue P2 connector. After that, you will count the flashes that appear on your dash! The length and amount of flashes will tell you your code!. Here is a code chart for OBD0 Honda codes! 

Check out this video about Honda OBD0 codes by clicking here! 

To pull Toyota codes, you need to turn the key to accessory mode so that the dash lights illuminate. Then you open your hood and find the diagnostic port on the passenger side of the engine bay. After that, find the copper wire and a paper clip to short the TE1 and E1 terminals. Then see what lights flash on your dash! The amount and length of flashes will tell you your code! Here is a code chart for OBD0 Toyota codes!

Check out this video about Toyota OBD0 codes by clicking here!


In 1988, OBD1 was invented by GM. It was used on an airplane! OBD1 check engine light system specifically focused on “emission control systems”. OBD1 systems were eventually found obsolete. DCCs were read through blinking patterns.

For example, if the check engine light blinked a certain amount of times, it would mean a certain code, that could be read by the mechanic working on your car.

How do I pull the obd1 codes?

Pulling a Honda OBD0 and ODB1 code are very similar. First, you must have your key turned to the accessory mode. After that, you need to find the diagnostic port along with the 2-pin connecter. This is located under the passenger side dash. Then you need to insert a jumper wire or a paper clip into the other pin connecter. 

Once those tasks have been completed, you then turn your car on to the check engine light flashing. Those are telling you your code. Here is a list of Honda Acura OBD1 codes. 

Check out this video about Honda OBD1 codes by clicking here! 

To find Toyota OBD1 codes you first need to find the diagnostic box on the passenger side of the hood. Then find a jumper wire and connect it to the TE1 and E1 terminals. After that turn your key to accessory mode. Then watch the check engine light flash and the light of the flashes and the number of flashes will tell you your code! Here is a list of Toyota OBD1 codes.

Check out this video about Toyota OBD1 codes by clicking here!


OBD2 was invented in 1992, however, it did not become popular until 1996. Volkswagen and GM had their own OBD2 system before most cars. About two years before it was mandatory, by law, to have cars with OBD2. It was invented by CARB (the California Air Resources Board). 

The original OBD2 diagnosis systems had a LED screen, cable, and a mini keyboard. Over the last decade or so, many OBD systems have gone with a Bluetooth interface for their connection. Scanners like Alltel, Snap-On, and Bosh have come a long way with the ability to diagnose programs and calibrate the most advanced system for the modern automotive technician. 

There are also very simple scan tools that the home mechanic or average joe can buy off of Amazon for relatively cheap. We recommend this not too expensive scanner off amazon for basic automotive tasks. 

How do I pull OBD2 codes?

Did you know that all cars made in 1996 and newer have obd2 codes? They can be diagnosed using a diagnostic scan tool. OBD2 codes communicate using parameters or PIDs. Currently, there are five different OBD2 communication codes. There is the KWP, PWM, VPW, ISO 9141, and CAN codes. 

Chrysler, Cadillac, and other European products use  ISO 9141. Ford products use SAE J1850 PWM. Click here for a list of the OBD2 codes and what they stand for. Check out this demonstration of pulling OBD2 codes with a scan tool by clicking here! 

different codes:

Diagnostic trouble codes are classified by letters and numbers such as p codes, Abs codes, TPMs codes, and OEM codes. In the beginning, OBD codes were only required to show you powertrain codes. Later on, they invented the ability to show more! 

Each letter and number in OBD codes mean different things. The numbers stand for what is happening with your vehicle and the letters stand where it is happening. 1 and 2 stand for fuel and air metering, 3 is for ignition misfiring, 4 is for emission controls, 5 is for speed control, 6 is for the computers, and 7,8,9 are all for transmissions. The zero stands for SAE and acts as a placeholder. B is for the body, which includes your AC and airbags, C is for chassis, your antilock braking system, P is for power train and U is for User network. 

There are a couple of ways that check engine lights can be cleared. One way is a scanner and repair! First, a technician would use a scanner to diagnose the issue. Then, they would repair it.

Check Engine Light
Check Engine Light

 The Check Engine light strikes fear into the hearts of some drivers and are totally ignored by just as many. Just what it means is a mystery to most of us in Chico CA. I have even seen some customers have the light covered up with their favorite picture of their child or pet. Things do not need to be this way, Tedious Repairs is here to help. 

First off, if your vehicle’s Check Engine light is flashing, that means that something is wrong that could cause severe damage to the catalytic converter or other components. DO NOT KEEP DRIVING THE VEHICLE! Get that taken care of right away, before you cost yourself thousands of dollars or worse, a new engine. If your Check Engine light is flashing, you shouldn’t drive at Chico highway speeds or even at all. You will need to call a tow truck of your choice, we use North Valley Towing or Brown’s Towing. I would rather spend $70-$100 on a tow them cost myself a new motor.

If the light is glowing steadily, you should book an appointment with us online or come drop it off as soon as possible. You can always just call to schedule an appointment with your Chico service advisor to get it checked out at 530-826-4275.

Vehicle Diagnostic Report
Diagnostic Report

Some more information from Tedious Repairs on how the Check Engine light works may be informative. Most of your vehicle engine functions are controlled by a computer, not surprisingly, called an engine control computer. The computer is able to adjust many engine parameters for environmental conditions, engine conditions, and even the way you drive in Chico.

In order to make these adjustments, the vehicle computer relies on a network of sensors to provide data. The computer knows the proper operating range for each sensor. When a sensor reading is out of range the computer runs some tests and may turn on the Check Engine light.

The vehicle computer will also try to make adjustments to compensate for some readings. If it can do so, it’ll then turn off the Check Engine light.

If the problem can’t be resolved then the light will remain on and you should get your vehicle looked at Tedious Repairs. Your friendly and knowledgeable service technician will plug a scanner into the onboard diagnostic port and read the trouble code stored in the computer. The trouble code will give your Tedious Repairs technician a starting place as he diagnoses the cause of the problem.

Engine Light 

Is Your Check Engine Light On?

check engine light

That check engine light is annoying, isn't it? Don't worry, we can help! At Tedious Repairs, we can run diagnostics and repair whatever issue is causing the check engine light, whether it's overheating, fluid leaks, electrical problems, and more.

To schedule an appointment, use the contact information below. You can call or text, email, or schedule an appointment quickly and easily using our online app.

Thanks for visiting and keep coming back for more great auto repair advice!

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