Adjust Tank Sensor Calibration (MJ1998)

I installed a different instrument cluster with FIS (multifunction display) and additional gauges in my A4 (year 1996). Everything works as it should, except that the fuel gauge and the trip odometer display incorrect values, showing too much.

I've tested various values with adaptation channel 1, but I had to set it to 0 to get an approximately correct display value. However, the fuel gauge and the remaining mileage display still show too much. The remaining mileage is about 150 km, and the fuel gauge still shows 6-8 liters too much.

I read on http://wiki.ross-tech.com/ that an additional procedure needs to be performed. What does that procedure entail?

"Does anyone know what this procedure looks like? It's really annoying to drive around with a faulty fuel gauge."

A friend of mine has a G4 VR6 instrument cluster (KI) in his Vento; he did the initial calibration using a standard resistor (I think around 30 ohms), and I then fine-tuned it using VAG COM. The KI even provided direct access to the adjustment channels .

The thing is, the smaller the resistance, the fuller the tank. If the reading is too low, or if the resistance is too high, I would simply add an additional resistor.

However, I need to reduce the resistance, but since the adjustment channel is already at 0, I can't go any lower. Also, I'm not receiving any direct assistance from the AI.

Typically, in this type of model, a value (likely a resistance) is simulated using a specific test set, and the display is then adjusted based on that value. In newer models, the user simply specifies the amount of liquid being added in liters, and even that feature has been gradually phased out.

In your case, I would rather check the sender, because it seems to me that it is malfunctioning, especially since you have already adjusted it almost to its maximum.

When I reinstalled the old AI unit, the display was correct again. The old unit showed a value of 128, while the new one displayed approximately 1/5 more than that value.

The old KI (instrument cluster) was from 6/96, and the new one is from 12/96. Could it be that Audi installed a different fuel sender? I also had to adjust the fuel consumption display to 115% so that it shows me the correct instantaneous fuel consumption.

What was the resistance value used/being used?

bastion wrote:

If I reinstall the old AI, the display will be correct again. The old one had a value of 128, while the new one displays approximately 1/5 more than that value.

Part number: KI (old version) vs. KI (new version)?

bastion wrote:

What was the size of the resistor that was used/is being used?

A special test device is used, so it's only a presumption that it's a resistance value. Otherwise, please refer to the repair manual.

I don't have access to the repair manual. I'm just a hobbyist mechanic.

The part number for the new AI (VDO) is 8D0 919 033N, while the old one (UK NSI) has the number 8D0 919 033A.

And if you simply connect the resistor in parallel with the fuel level sensor? That should correct the offset, or rather, cause a global shift in the values.

That won't do anything. Resistors don't simply add or subtract. The value of the largest resistor in the circuit always applies, and smaller ones are effectively ignored. In my case, that's the fuel tank sensor.

My problem is that the fuel level sensor seems to have too high a resistance for the control unit (KI), and the adjustment range isn't quite enough to compensate for it. Perhaps the control unit also needs to be set to a specific value, and since I haven't done that, it's now showing me nonsensical readings.

bastion wrote:

That won't do anything. Resistors don't simply add or subtract. The value of the largest resistor in the circuit always applies, and smaller ones are ignored. In my case, that's the tank sensor.

Um...

http://www.elektrotechnik-fachwissen.de/grundlagen/reihenschaltung-widerstand.php

That won't do anything. Resistors don't simply add or subtract. The value of the largest resistor in the circuit always applies, and smaller ones are irrelevant. In my case, that's the tank sensor.



Such nonsense . For resistors in parallel, the following applies: 1/Rtotal = 1/R1 + 1/R1 + 1/R3 +.......+ 1/Rn -> because when resistors are connected in parallel, you have to calculate with conductances.

If you only have two resistors, you can also calculate the total resistance using the product/sum method. This means that when two resistors of the same value are connected in parallel, the value of each individual resistor is halved. Assuming: 5 Ohms, 2 pieces: 5 x 5 = 25; 5 + 5 = 10; 25 / 10 = 2.5 Ohms.

For those who are interested: it's exactly the opposite with parallel capacitors.

EDIT: f*** - Sebastian was faster

Argh!!! I Honk. Yes, of course.

Does the AI's coding match? The installation period seems correct.

I copied it exactly, even the kilometers .

AI malfunction?