BMW engine coolant temperature сorrector

Hello!

Everyone knows the problem of fairly modern BMWs, and I think not only BMWs. The problem is the boiling of the engine to 108 degrees Celsius at low loads (such as traffic jams, waiting in a parking lot, etc.). The cycle is simple – when temperature reaches 108C, ECU resets the temperature to 105 by turning on the fan (in winter it doesn’t even turn on sometimes) and the electric pump to higher speeds, and then again in a circle.

Of course, when you start driving actively, the coolant temperature drops harshly and the oil temperature drops next. Obviously, it is dangerous to accelerate on an overheated ICE. Therefore, engineers have made a safer engine cooling cycle at power mode. A high operating temperature of an ICE means high pressure in the coolant system, oil coking due to overheating, low pressure in the oil system due to overheating of the oil, and many more reasons. These reasons are described in many places and many people have encountered them. It is clear that there are no critical values, but why should we risk.

My coolant reservoir exploded when I was just in the parking lot. I was watching how the oil temperature arrow for 30 minutes rises from 105 to 110 degrees. I changed the lid of the reservoir 4 days before. I am sure that if the coolant temperature was 85 degrees, this would never have happened.

Cold thermostat

This is a dubious decision for N54 / N55 engines, since there is an electric pump and if the thermostat opens earlier than necessary, the system will not turn on and the liquid will flow sluggishly through the radiator with practically no cooling and, of course, without cooling the engine.

There is an effect from it. It reduces the temperature in traffic jams by an average of 5-10 degrees (I collected feedback from the people who installed it).

Additional radiator

They install it for hot countries. Information from unverified sources says that there is a slightly different firmware, and this firmware regulates the temperature modes of the engine in a different way during operation.

There are too many problems for me. Therefore, I have discarded this option.

BMW engine coolant temperature сorrector

This is what the manufacturer calls it 🙂

Outwardly, it’s just a weird thing. But at the same time, it’s well built! It’s very easy to install in the engine and this thing becomes invisible for a layman. It uses factory connectors everywhere, and the wires tucked into a black cable duct.

You install the device on the upper hose of the radiator. It connects in-between the native temperature sensor. One end to the ECU, the other end to the DME. This solution is very convenient. Simple and efficient.

On modern cars, the following cooperatively working devices achieve temperature control:

Controlled thermostat
Radiator cooling fan
Radiator shutters
Variable displacement pump

DME activates all of them when the coolant temperature approaches 108-110 degrees. Alltogether, and not each separately. In contrast to the classic cold thermostat: when it is open, the cooling fan is off, and there is no point in this (purely academic case, in practice, a cold thermostat on “hot” firmware is really useful).

If we talk about good cold firmware, then it must correctly manage all the listed components. In other words, chip makers must intervene in the operation of important operating modes of engine components. Therefore, I have great doubts about the existence of such a firmware.

Now about the BMW engine coolant temperature corrector. As I already wrote, all engine temperature control mechanisms are activated when the coolant reaches the upper temperature threshold. According to the algorithm specified by the manufacturer in the DME. The thermostat corrector only shifts this threshold down by 12-15 degrees and does not affect anything else or interfere with the operation of other devices.

The point is this: increasing the transmitted temperature from the sensor to the system within 15 degrees. What does it do? Cooling fan turns on; electric pump works more intensively (if you have such option). The temperature seen by the system is corrected (shift upwards by an average of 15 degrees). Now, through the hidden menu, the average temperature is 110 degrees, but in fact, it is 95.

When the temperature reaches 93-95 degrees (in my case), this device corrects sensor readings by 12-15 degrees. In the 7th test, you can see a surge in readings. Starting from a certain point, we see that the temperature is 12-15 degrees higher than it actually is. The entire cooling system starts to operate at a lower temperature and operates normally. More information can be found on the internet.

I think this option is excellent, and I see no arguments against it. This is a ready-made, tested product for good money. Surely, this can be implemented through an engine firmware update, but not all engines have it. For myself, I chose this method, it seems to me simpler and more practical, and the installation of the device takes 15 minutes. You can remove the device at any time by yourself.

I’ve been driving with the BMW engine coolant temperature corrector for about 2 months now. No problems at all. The oil temperature dropped and in urban conditions, it is about 100 degrees Celsius. I don’t see real readings of the coolant temperature, apparently, it dropped by the same 12-15 degrees.

Hello to everybody! As it usually happens – predicted breakdowns begin to come out. Repair of the cooling fan caught me at the hottest part of the season.

On 407 forums, they often write that cooling fan often breaks down, because of winters when all sorts of rubbish gets in and eats away the motor board. The price for a new one is not very humane. Therefore, I decided to fix it.

The fan itself is not as simple as it was set before. It does not have the concept of 1 and 2 speed-but there is a PWM signal that controls the speed of rotation.

I found the site — electrorefite, where the guys sell the boards, which were made and modified by themselves. They give a year warranty.

I will not describe the process of removal and installation, since there is a lot of information.

I only had to re-solder the brushes. Finally, I checked the work on the car.

But not without a fly in the ointment! When removing the fan itself – the air conditioner radiator was hit. I decided to rinse it with Karcher – and at the place where the motor contacted the radiator, the cells simply fell down. For now the radiator is working, but the question of replacing it will soon remind of itself. But while there are other things to spend money on, I decided to wait until it completely dies.

Since the purchase of the car, the fan worked only at max revs when the climate control was turned on. The reason for this was a not working ECU of the fan. I decided to change the ECU, I found out on the forum that now improved ECUs are installed (I also found replacement specialists there).

Major improvements:

Reverse polarity protection.

Two powerful output transistor stages.

Improved heat sink and resistance to mechanical destruction due to a solid board on aluminum base.

Improved anti-corrosion protection due to silicone filling compound.

Repair of the electric fan for Peugeot & Citroen 2002 – 2007

In general, it was a week and a half ago. I remember there was a downpour but hot. I was driving. I was relaxing under the air conditioner when suddenly I was hot in my face. A strange and unpleasant sound appeared in front of the car. I went out… The fan broke down. I started surfing the internet. What a miracle! A board available! I bought it and installed. Everything is working!