Since the car's computer, or ECU, still has some current, disconnecting the battery for a short time may not be enough to reset the ECU. After disconnecting the engine, wait at least 15 minutes to ensure the system is reset. As mentioned earlier you can reset your car’s ECU without disconnecting the battery.
How long do you disconnect battery to reset computer?
Because some of the electrical current is preserved in the computer for a while afterward, most sources recommend leaving the battery disconnected for at least 15 minutes to make sure the computer forgets the code before you reconnect the battery.
Is it OK to disconnect car battery?
You should never attempt to disconnect your car's battery while your car is powered on. We'd also recommend using safety equipment, like gloves and safety goggles, if you have them on hand.
Do you need to disconnect battery to change crankshaft position sensor?
Connecting or disconnecting the battery is a no brainer. If there's danger of shorting battery power to ground during the repair, unhook it or pay the price later. In the case of crank sensors, there is no powewr to that connector if the key is OFF. In this case, makes no difference.
Related Question Will disconnecting battery reset car computer?
Is it OK to just disconnect the negative terminal?
No. The battery will not cause any problems when changing the plugs. The one thing to avoid is accidentally dropping a tool and having it contact the positive battery terminal and the car body. If this occurs, you will get a spark and possibly blow a fuse.
What terminal do you take off to test alternator?
Do I disconnect the positive or negative to check the alternator? Disconnect the negative battery cable before testing an alternator. Instead, use a voltmeter to perform a basic and safe test.
What does clearing codes on a car do?
When a code clears, you know that the vehicle has been restored to good working order. However, there could be occasions when clearing the codes manually is part of the repair process. For example, a check engine light can be triggered when the gas cap isn't tightened correctly.