ECU weight
A reliable ECU ground is very important for the proper operation of the engine management system and the engine as a whole.
It would seem to be a primitive and reliable design that can serve well for years. But in reality this is far from the case.
It is very difficult to list all the possible problems that can arise due to poor ECU mass, since it can affect anything. But the main problems can be divided into two points:
- Incorrect collection of information from engine control system sensors. Personally, I had to deal with incorrect MAP sensor readings. It gave inflated barometric pressure readings precisely because of the poor weight of the ECU.
- Since almost all modern engine control units are able to adapt to real operating conditions, as a result of incorrect collection of information from sensors, adaptation leads to engine malfunctions. This is why for many, after resetting the adaptations, the engine begins to work much better. But then the problems return as the ECU adapts again. And again this does not happen quite adequately.
Where is the ECU ground located?
The ECU mass is usually arranged like this. Separate ground wires are removed from the ECU connector and connected to the engine via the starter mounting bolt. Ground wires are usually black.
In the photo, the thick wire is from the battery, and the thin wires are from the ECU and speed sensor
Everything is simple and reliable. But in reality, over time, the voltage begins to drop in this section of the circuit, slowly but surely, disrupting the operation of the system.
Therefore, this unit must be periodically checked and maintained. We will look at how to do this further.
Troubleshooting
For uninterrupted operation of the battery, the system must be equipped with good quality wires; in this case, copper wires are the most suitable, since they have the best characteristics when operating under voltage.
The thin positive wire coming from the generator must be replaced with a thicker wire.
To protect the existing mass and ensure longer and more trouble-free operation, it is necessary to treat all existing connections and terminal contacts with a special lubricant that has an anti-oxidation function.
You can strengthen the mass by placing additional mass near the generator. Of course, you should not use a thin negative wire to connect to the car body; it is better to use a thick wire. The result will be better, and if problems arise with the main wire, the additional one will be able to start the car, and again you will not have to listen to the clicking of the relay.
As a result of the procedures performed, the car will start more confidently. We will eliminate the problem of frequent battery discharge, which will avoid the loss of much-needed volts for the car and, as a result, ensure the most stable and sufficiently high voltage coming from the generator.
Source
Weight between engine and body
Line “31”, popularly called “ground”, “minus” or “negative circuit”, is very important for a car. And not only for electrical equipment, but also for many other systems, including the engine or automatic transmission.
Almost all cars have a single-wire on-board network system and the role of the “minus” in this circuit is played by the metal parts of the body. This greatly reduces the number of wires and reduces the cost of the car.
It turns out that all participants in this chain have their own connection to the body - instrument panel, headlights, ECU, engine, etc.
Despite the visual integrity of these connections, over time, due to oxidation and corrosion, the contact slowly and imperceptibly deteriorates, which leads to voltage drops when powerful consumers are turned on or disruption of the system.
I would divide the mass connections into main and local. Let's say that the connection of the head light masses is local and if this connection is disrupted, only the head light will suffer. But if the ground contact from the battery to the body is broken, the entire on-board network will suffer, and this may cause problems in the operation of the engine and other important components and assemblies.
This is how the voltage of the on-board network with problematic masses looks like on the diagnostic graphs
And here is the graph after mass prevention of battery - engine - body
Therefore, a reliable engine-body mass is very important for the proper and trouble-free operation of the entire vehicle.
And the mass of the ECU - engine is even more important, since the voltage in the engine control system does not exceed 5 V. Therefore, this further encourages owners of cars with an engine management system to take the issue of mass more seriously than owners of carburetor cars, where the voltage is 12 -14 B. Because the lower the voltage, the greater the damage from losses in the circuit.
In general, the ground chain must be maintained in perfect condition. It's like an axiom.
Next, let's look at where the engine-body mass is located and how to check it.
Where is the mass of the ECU on the VAZ 2114
Electricity is vital to running a car. Power comes from the battery through the positive and negative wires. The first of them provides 12 V. The second is connected to the car body. It is called ground or neutral wire.
Battery weight
For proper operation of the electronic control unit, sensors, instruments, headlights and much more, it is important that the mass on the brains of the VAZ 2114 is reliable. In practice, we are talking about the fact that in some places on the body the neutral wire terminals are screwed with nuts to welded studs.
Although at first glance it seems that the mass of the ECU on the VAZ 2114 should be reliable, in fact this is not the case. If the mass wire is not given due attention, then it gradually ceases to function normally. There may be several reasons for this:
- When painting, the contact between the terminal and the housing may be disrupted.
- Gradually the nut unscrews.
- Contact is broken due to oxidation or contamination.
There are connections to the body in several places. You need to know where the mass of the ECU on the VAZ 2114 is located and regularly check for contact. In order to make it more reliable, it is recommended to use a castle washer between the terminal and the housing. Due to the presence of sharp areas, it provides high-quality contact.
Castle washer The location of the ground depends on the model of engine used. If we are talking about a model with a volume of 1.5, then the following arrangement is used:
- The first terminal is located under the dashboard on the steering wheel mount..
- The second is located on the heating motor housing on the left side.
To know where the ECU mass is located on models that use a 1.6 liter engine, you need to remember the following:
- If you look inside the instrument panel, you can see the first pin on the left side. It is located above the relay/fuse box .
Weight inside the dashboard
- The second is located above the left screen of the center instrument console. It is located on a welded stud.
The mass is not protected in any way from contamination or rust. It must be inspected regularly, and if necessary, cleaned and tightened the nut.
Where is the mass of the engine - battery - body
On most cars, the engine-body mass has a primitive appearance and is made of two pieces of cable connected together by crimping on the negative terminal of the battery
This crimp connects two wires. One goes to the engine and is secured with the starter mounting nut...
...and the second one on the body in the area of the left wing
It would seem that this is the simplest and most reliable chain that will serve well for years. But this is not at all true and it’s all to blame for the weak points in this design, which do not withstand the test of atmospheric influences.
Bad mass
Flashing rear lights or turning on several light bulbs at the same time is a common occurrence for owners of “fours”. In addition to poor contact, the cause of such “color music” can be a bad mass.
The negative wire of each of the rear lights comes out of the connecting block of wires (chips) and is attached to the body next to it. Periodically, this connection oxidizes and the contact disappears (the circuit opens). Laying a new ground wire allows you to return working dimensions, turn signals and PTF. The photo shows the exact location of the ground wire for the rear lights.
In headlights and side lights, the design also includes mass. Over time, the mass disappears and the circuit opens. There are different reasons why the rear lights of the VAZ 2114 do not light up, but any car owner can eliminate each of them. Restoring the ground wire to the main wire braid going to the headlight unit does not take much time.
How to check mass on a car
In fact, only a small group of motorists pay enough attention to this issue. Others begin to think about it when, when the cooling fan or headlights are turned on, the engine speed begins to sag, or when the rear window heating is turned on, the engine begins to tremble, transmitting vibration throughout the body.
But even at this stage, many limit themselves to a banal inspection and tightening the ground connection nuts on the engine and body. Everything is screwed down - that means everything is in order.
Then the car begins to jerk for no apparent reason, idle speed freezes, misfires, security system glitches, and so on, until the starter fails at the most inopportune moment. But even here, many will not go check the masses, but will run to the store for a new starter. After all, the wire to the starter is intact and there is voltage, but it, a radish, does not turn.
Replacing the starter, of course, does not help. As a result, the still-living battery goes into recycling and the situation seems to have improved, but after a couple of days the starter fails again and you begin to believe in brownies and otherworldly forces that have nothing better to do than cause damage to someone else’s car.
But, fortunately, reason wins and the advice of a good man is remembered - to check the masses.
Again, what's so difficult about this? It is necessary to check the resistance from the engine to the body.
