Will a ECU drain your battery?
A failed ECM power relay can also cause a battery drain or dead battery. If the relay shorts it can leave power on to the computer, even when the vehicle is turned off. This will place a parasitic drain on the battery, which will eventually cause it to go dead.
How can a battery damage an electronic control unit ( ECU )?
As such, circuity in the car drops the 12/13.5 volts to the 5 volt level that the ECU can handle. Now, if something goes wrong with this voltage-dropping circuity, or the alternator is defective and generating too high a voltage (which would also fry your battery in time), then too high a voltage may go to the ECU, thus damaging it.
How does the ECU work in a car?
The ECU in a motor vehicle (aka: Computer), utilizing a number of sensors on the engine (oxygen content of exhaust, crankshaft position, etc.), controls various engine parameters (ignition timing, air/fuel ratio, etc.) to insure the engine is always running at peak efficiently.
What kind of memory does an ECU have?
Pretty much all modern ECU’s have either flash memory or “non volatile RAM” (pretty much like teh “CMOS memory” in your PC), which holds codes and other things the ECU wants to remember even if the battery is disconnected or discharged. Nearly anything produced since the 1990’s will have flash memory.
When to use reverse polarity on an ECU?
Reverse polarity – This might be the scenario when you car is battery down and you are trying to jump start an ECU. Always connect the positive leads of both batteries first, then the negative leads. This will ‘soften’ the flow of power through the earthing system and prevent power surges or spikes.
What happens to the ECU when the battery is removed?
The car ECU maps aren’t held in volatile memory, so will not be affected by removing the battery. if it did, then your cars ECUs would all reset to factory every time the battery was removed. Secondly, how long does it take for a car computer to reset?
Can a bad ECM drain the battery all at once?
This is where the voltage regulator comes in, it allows the alternator to maintain the correct amount of voltage so that the alternator does not exceed the amount of voltage supplied to the battery. Too much voltage supplied to the battery and components can begin to fry, too little and the battery will not charge at all.
What does the ECU do in a car?
The ECU, or engine control unit, is a major component of your car’s onboard computer. It’s used to regulate many systems and subsystems in your car’s engine, drive train and other major components. There are many symptoms that can be associated with a faulty ECU. Here are some ways to tell if yours is damaged or faulty.
What to do if your ECU goes bad?
ECU Computer Diagnostics. If you suspect that the electronic control unit in your vehicle is damaged, or is going bad, you should immediately take your vehicle to the nearest dealership, repair shop or service center.