@Michael II: Adaption channels and coolant thermometers

Hi Michael,

Is there a way, using a diagnostic tool, to change the behavior of the coolant gauge on diagnostic-relevant combination instruments (specifically part number 6K0920801E)?

I find this nonsensical "plateau function" particularly annoying, because the part always indicates 90 degrees as long as the temperature is between approximately 75 and approximately 105.

Can it be parked using parameters?

Can this device possibly be forced to display the oil temperature instead of the water temperature, using software, if there are sensors for that?

Best regards,

Jan

Hello Jan,

The fuel gauge can be influenced. Unfortunately, the coolant temperature is not available.

Hi Michael,

How does this work with the fuel gauge?

Influence on deviation from linearity, or simply adaptation to tanks of different sizes? Or the threshold at which the warning light comes on?

My ad is also not really suitable for the description - the first quarter is much longer than the last.

Best regards,

Jan

Hello Jan,

You can adjust the offset of the level sensor. I'm looking for the service/drain channel for your Ibiza.

Hi Michael,

thanks, that would be great!

Best regards,

Jan

Hello Jan,

Select "Adjust" in the instrument panel. By changing the values in channel 30, the fuel gauge is adjusted.

Hi Michael,

thanks!

Best regards,

Jan

I'm revisiting the topic of the "Plateau Function" on the coolant temperature gauge here. So, the display always shows 90° between 75° and 105°. Presumably, this is done to avoid overwhelming the average user with temperature values that would already be confusing. The number of people who can no longer get to the workshop in the winter (my car doesn't get warm enough) probably gives VW a good reason for this decision. However, I'm still interested in the exact temperature value. Apparently, there is no way to reset the display via software. Does anyone see a chance to achieve this through hardware (by bridging the electronics)?

mcgregg

mcgregg wrote:

However, it seems there is no way to restore the display using software. Does anyone see a chance to achieve this through hardware (by bridging the electronics)?

Hi,

I find this hopeless, as the needle is moved by a stepper motor. This, in turn, makes the underlying electronics essentially indispensable.

IMO, it would be possible to only measure the voltage across the load, which would be highly impedance, and, for example, display the oil temperature according to Jan's method via an additional display without a plate function, in parallel with the normal instrument.

Hello everyone!

That AI in my "vintage A3" probably has a lot more to offer than your modern cars.
When I compare the analog instrument readings with the digital VAG-COM measurement values, I can detect a slight deviation from around 70°C, but not the extreme plateau function described here. The good thing is that I can also still recognize a certain degree of variation within the temperature range between 75 and 90°C, even though the displayed values don't always perfectly reflect reality.
I've never experienced temperatures above 90°C, so I can't comment on anything beyond that. I have, however, never heard my fan before during the height of summer.

Greetings
Alex

Hi,

Since I have the oil temperature gauge, the plateau of the other gauge no longer bothers me at all. With this, you get a more precise reading of the engine's temperature than with just the water temperature. If the cooling system is having problems, this will also be reflected in the oil temperature, and you will be able to detect this much earlier than if the water temperature simply reaches its normal operating range.

Therefore, it is more consistent to display the oil temperature instead of a second water temperature display.

Best regards,

Jan

Hi Jan

Sorry, but if you had ever experienced how quickly a motor on a country road can overheat when the water pump fails, you would know that the oil temperature increases dramatically.
The temperature is rising rapidly within seconds. The engine is overheating before you notice it at the oil temperature gauge.
Even if you stop immediately afterward. The engine heats up in such a way that cooking is almost impossible to prevent.
Experience the difference with a gasoline engine, while the TDI might be slower due to the lower operating temperature.

It's worth mentioning that the timing belt replacement was also due shortly after.

In normaler Betriebssituation sieht es anders aus, aber es sollte keine übermäßige Temperatur auftreten.

Hi,

In such a sudden drop, nothing seems to help, even a water thermometer without a plateau might be too slow.

I was more thinking of creeping errors, meaning slightly higher temperatures under similar driving conditions, and that's exactly where the oil temperature comes in handy.

A natural remedy is, of course, not a cure-all.

Best regards,

Jan

ulf wrote:

However, it seems there is no way to restore the display using software. mcgregg wrote: Does anyone see a chance to achieve this through hardware (by bridging the electronics)? Hi, I find this hopeless, as the needle is moved by a stepper motor. This, in turn, makes the underlying electronics essentially indispensable. IMO, one could at most measure the voltage across the load, which would be very high impedance, and, for example, display the oil temperature according to Jan's method via an additional display without a plate function, in parallel with the normal instrument.

Hello Ulf!

How do you get to the stepper motor? Have you ever taken the instrument gauge out? I've been carefully observing my coolant thermometer on the traffic light. It rose very slowly, and it seemed very "stepless".

mcgregg

mcgregg wrote:

How do you get to the stepper motor? Have you ever played the instrument outdoors?

Yep! The 1997 Golf AFN, 2001 Ibiza ALH, and 2004 Polo ASZ – all use stepper motor instruments.

Hi,

Quote:

It rose very slowly, and it seemed very "stepless".

"A stepper motor" only indicates the type of drive, not the size of the steps. They can be so small that a human cannot perceive them, even though there is a step movement and not continuous movement.

A good example is printers that use stepper motors to feed or eject paper – even in this case, you can't see anything happening with the faster models.

Best regards,

Jan