Does Car Have To Be Running To Use OBD2 Scanner

Taking your vehicle down to the garage to get the annual tuning done is becoming really outmoded nowadays. That is because of the introduction of an advanced high-speed computerized system called OBD2 (On-Board Diagnostic) scanner.

This system has the capability of correcting the ignition and fuel mixture automatically at each crankshaft revolution. It made things much better than the past few years.

However, there are still some questions waiting to be answered. Does the car have to be running to use the OBD2 scanner? How can you use the OBD2 scanner correctly after acquisition”? 

Before getting into the answers to these queries, let’s have a look at what an OBD2 scanner is and what are its functions. 

What Is OBD2 Scanner?

An OBD2 code scanner is a second version with the Diagnostics tool On-Board. This handheld computerized device can interact with different autos launched in 1996 and later. 

Earlier autos utilize ancient diagnostic systems which differentiate depending on the manufacturer of the car. Applying an OBD2 scanner is reasonably fast, and accessing codes only needs a few minutes.

Function Of OBD2 Scanner

OBD2 Scanner monitors different engine functions. If the engine of a vehicle experiences malfunction, the CEL (Check engine light) comes on. 

An OBD2 scanner can efficiently access the proceeding trouble codes inside the diagnostic computer, or powertrain control module of the vehicle. 

Additionally, it can also clear all the codes and highly assists in removing and diagnosing the malfunction.

Plus, it should be used according to the instructions of the manufacturer. All OBD scanners simply plug into the 16 pin DLC (Data Link Connector) socket in the vehicle pivoting on the model. These can be present beneath the dashboard on the side of drivers, and behind the panel in the center console.

What Type Of OBD Is My Car?

The onboard diagnostics or OBD of your car are computers that specifically monitor the engine for any malfunction or abnormalities. It detects even minor issues and simply triggers the car engine light as well as other essential notifications on the dashboard perfectly.

The most widely used is OBD1 and 0BD2 majorly. You may want to explore which type of OBD is in your car. How Do I Know What Type Of OBD Is My Car?

If your car was made in 1996 or later, it will definitely contain 0BD2, which means that you need an efficient OBD2 scan tool for communicating with the diagnostic system of the car. As OBD1 isn’t standardized, its scan tools are typically available for particular models and brands. Therefore, the particular scanner you need would be different.

Although OBD1 & OBD2 almost work the same, there are some clear differences between both these scanners. The most essential thing is the interface which is different in them. OBD1 has a specific interface for each manufacturer. 

On the other hand, OBD2 has a universal one that makes it quite convenient to make a smooth connection with the diagnostic system. It is more advanced and hence results in providing more diagnostics to your car.

OBD 1 cars usually do not have MIL (Malfunction Indicator Lamp), which majorly refers to as the “CEL (Check Engine Light)”. OBD 2 scanner has more gizmos and sensors that perfectly throw a code. These sensors are more probable to throw the code in an OBD2 car rather than in an OBD1 car.

Moreover, if there is no OBD under the dashboard and you have the diagnostic port in front of your power distribution box under the hood, it means that your scanner is OBD1. Similarly, the OBD2 standard probably defines the shape of the diagnostic socket.

One of the most efficient and quick ways to determine which PSM/ECU you have is finding out its location. If it is not present on the passenger internal fender under the hood, then keep in mind that it is not OBD2.

Does Car Have To Be Running To Use OBD2 Scanner?

Based on the car manufacturer, you may turn the engine on and let it idle. Make sure the car is in the on position not running for scanning it.

As long as everything is connected and installed completely, you will need to change the engine ignition key into the ON position & simply run the scanner. Otherwise, there’s no way of examining live data if the switch is off.

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It gives you the ability to attain real-time data so that you can test the potentially defective part easily rather than swapping it & seeing it over and over again if that is fixed or not.

If you face any difficulty with using this scanner, you can contact tech support as well and they will surely help you. All in all, CRP123 is the best product for diagnosing the vehicle efficiently. See the latest price here.

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How To Use OBD2 Scanner With Push Button Start?

The very first step to getting in your computer is to plug properly into the port that is present under the dash. Then, simply port in the plug & power on the particular scanning tool. Some scanning gadgets are powered externally and a few of them are operated on the vehicle power.

Push the start button, turn the engine ON and let it idle. Simply plug the scanner in the port, In order to get information from the computer, scan the car simply to find out what the issue is. After that, follow all the directions shown on the screen. It’s a quite simple and straightforward process. 

You should be capable of scanning the code “Ready on” with the car. On the other hand, you can also press the start button twice without pushing your foot on the brake. The push start button is especially for OFF or ON when you do not have a traditional key of ignition in your car.

It will highly assist in finding out what is the main problem. Once you get the codes, simply fix them accordingly.

Car Won’t Start After Using OBD2 (Why and Fix)

Are you confused about how you can fix it if your car isn’t starting while using OBD2? If you have been facing this issue for a long time and couldn’t find out the reason till now, it is just because of your busy schedule or carelessness in this matter. Well, let’s fix that.

The car can stop starting properly due to many reasons. But mostly it happens when either the connection got short or it’s attached inappropriately that is blowing the fuses. There can also be a possibility that the battery may not have sufficient juice.

If you were sitting in your car during scanning and then left the car door open along with the dome light on, there are chances that it might run low. In addition, low voltage and power can also cause these issues. Now, as you are facing this irritating problem and looking for a solution probably, we are here to help you.

Fixture: If your car does not start after using the OBD2 scanner, try hard reset. Simply take out the positive and negative terminal from your battery & make contact with each other. Do it for 10 seconds and place it back on the actual positions. Start your car and it’ll hopefully begin working.

Can You Use a Code Reader On a Car That Won’t Start?

Absolutely, yes! You can use a code reader if the car won’t start. It entirely depends on the OBD2 scanner. Sometimes, it can work by simply turning on the ignition. However, in some cases, you just need to start the engine & let it idle simply.

The car should be in the on position while resolving it. Anyhow, the Bluetooth scanner works completely fine with the off-engine but make sure that the key is on. Otherwise, it won’t work at all.

Can OBD2 Scanner Damage ECU?

The OBD2 scanner can cause extreme damage in ECU and create various problems. Yes, you read that right! But note that it only happens if the person is using it inappropriately. Make sure that you’re not purchasing cheap scanners just to save a little amount of money. 

Furthermore, they can destroy your computers entirely as you’re trying to plug it into the OBD port. If that scanner is not working well, it could badly short out the main computer. Keep in mind that faulty wiring can also cause great damage in ECU/DME.

All it takes is just a millisecond to leave drastic damage permanently. Furthermore, it can be caused by a defective device, a malicious or a bad app as well.

Related Article: Check Engine Light On But Car Runs Fine