How to Test an ECU with a Multimeter (4-Step Guide)
Content
Your car can break down and stop for various reasons, diagnosing these problems is essential to fix them. The problem could very well be the ECU. But how to check it?
To test the ECU with a multimeter, you need to follow 4 simple steps: 1. Set up the multimeter, 2. Conduct a visual inspection, 3. Connect and follow our testing guidelines, 4. Record the readings.
Embarrassed? Don't worry, I'll cover this in more detail below.
How to check the computer with a multimeter
Here are 4 simple steps to follow when checking the ECU with a multimeter:
Step 1: Set up your multimeter
The multimeter consists of 3 main parts:
– Display
– Selection knob
– Ports
Company display multimeter has four digits and the ability to display a negative sign.
Selector handle allows the user to set up the multimeter to read various values such as current (mA), voltage (V) and resistance (Ω). We have to plug two multimeter probes into the ports at the bottom of the display of the device. There are two probes, a black probe and a red probe.
The color sensor is connected to Com port (short for Common), the red probe is usually connected to mA ohm port. This port can measure currents up to 200 mA. Here V stands for voltage and resistance Ω. There is also port 10A, which is a special port that can measure more than 200mA.
First steps
Next, set up the multimeter to measure the current strength (mA). To be able to measure current, we have to physically turn off the current and put the meter in line. The first step requires a piece of wire, we will physically break the circuit to measure the current. Disconnect the VCC wire going to the resistor, add one to where it's connected, then connect the power pin on the power supply to the resistor. It's efficient Turns off power in the circuit. In the second step, we will connect the multimeter to the line so that it can measure the current as it comes in. streams through the multimeter to the printed circuit board.
Step 2: Visual Inspection
When we look directly, we need to take notes. First, we need to check if the ECU is working properly or not. We have to look outside to see if the ECU is cracked or badly damaged.
Attention: Please keep an eye on both sides, because even a small crack or signs of burning may mean that the ECU is faulty or inoperable. In the event of damage, the meter will be checked to ensure that it is connected to the ECU and that the test leads are properly connected to the port. After observing everything, you can start measuring with a multimeter.
Step 3: Start testing with a multimeter
You need to test each component with a digital multimeter. You should check the fuse and relay first and then do the current draw. A test should be done to make sure there is enough power going to the engine computer and to check the voltage going through the sensor and fuses. Make sure that power is supplied to the components when performing the test. (1)
The testing process includes the following steps:
- Leave the current on the A scale for AC measurement.
- Black test leads to Com port, the red test leads to mA ohm port.
- Set the multimeter clock switching on the scale A-250mA.
- Turn off the power to the test circuit.
- Connect the red probe in the direction of the (+) pole and the black probe in the direction of (-) in the direction of the current in the experiment. Connect the multimeter to the test circuit.
- Turn on the test circuit.
These are the steps to perform an ECU test with a multimeter. Pay attention to the index scales to get the best test results.
Step 4: Write down the reading
After the ECU test, we will see the results on the multimeter screen. For a digital multimeter, the result is easy to read. For analog, I will tell you the steps to read the measurement results.
- Determine the correct scale on the multimeter. The multimeter has a pointer behind the glass that moves to indicate the result. Usually three arcs are printed behind the needle in the background.
The Ω scale is used to measure resistance and is usually the largest arc at the top. On this scale, the value 0 is on the right, not on the left, as it is on other scales.
– The “DC” scale shows the DC voltage reading.
– The “AC” scale indicates the AC voltage reading.
– The “dB” scale is the least used. You can see a brief description of the "dB" scale at the end of this section.
- Write the stress scale index. Look closely at the DC or AC voltage scale. Under the scale there will be several rows of numbers. Check the range you have selected on the pen and look for the corresponding symbol next to one of these rows. This is a series of numbers from which you will read the result.
- Estimated cost. The voltage scale on an analog multimeter works similarly to a conventional pressure gauge. The resistance scale is built on a logarithmic system, which means that the same distance will show different changes in value depending on the position that the arrow points to. (2)
After completing the steps, we will receive the measurement result. If the measurement result exceeds 1.2 amplifiers, EUK is faulty if the result is less than 1.2 amplifiers, the ECU is working normally.
Note. The ignition must always be switched off when performing an ECU test for maximum test efficiency.
Precautions when checking the computer with a multimeter
There are a few things you should watch out for when you want to check the ECU with a multimeter. These precautions will ensure both your safety and the safety of the engine control unit, and they are as follows:
Gloves
If you are planning on using a meter to test the ECU, the first thing you should do is wear gloves.
Explore visually
It is extremely important to inspect the engine control unit and make sure everything is in working order.
Check multimeter
To get an accurate test of your engine control unit, make sure your multimeter is working properly and powered properly.
Ignition
When using a multimeter to test the ECU, make sure the ignition key is turned off.
ECU connection
With the engine running, do not disconnect the engine control units. Be careful when connecting the ECU terminal.
Summing up
The practice of measuring the ECU with a multimeter is a complex and time consuming process for the novice or inexperienced. This article will help you solve this problem. The above steps are the most important details to pay attention to during the practice of checking the ECU with a multimeter.
Before you go, we have listed a few multimeter test guides below. You can check them out or bookmark them for later reading. Until our next tutorial!
- How to test the ignition control module with a multimeter
- How to Read Analog Multimeter Readings
- How to test a capacitor with a multimeter
Recommendations
(1) computer - https://www.britannica.com/technology/computer
(2) logarithmic system - https://study.com/academy/lesson/how-to-solve-systems-of-logarithmic-equations.html
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