ARL Engine: How Speed Signal Reaches the Gauge.

Hello,

By installing an ARL engine into an Audi Cabriolet manufactured in 1996.
I'm still having the problem with the old tachometer.
is not yet connected.

In the engine wiring diagram, I can only find information about the speed sensor.
is connected to the control unit J248.
But how does the speed signal get to the speedometer?
It would be interesting to know the PIN.

I really hope this isn't being transmitted over CAN.


If anyone has any information, please let me know. Thank you in advance.


Best regards, Franz.

yellow5 wrote:

... I really hope this isn't being transmitted over CAN. ...

Depending on the donor vehicle, that might be the case. However, since you haven't mentioned anything about the donor vehicle, we're probably just guessing... Oh, darn -> it's broken right now .

yellow5 wrote:

I really hope this isn't being transmitted over CAN.

And even that shouldn't be a problem, as long as the speed signal isn't yet coming from wheel sensors, but rather from a sensor on the transmission. In that case, a splice would be the solution.

Otherwise, I can only refer to Bertil's post.

Hello,

The donor vehicle was a VW Bora, manufactured in 2002.
Engine code: ARL
110 kW

In the wiring diagram, several wires are shown.
Direction is towards the dashboard, but unfortunately, many of them are not labeled.

I hope that signal is included.

The speed signal is also transmitted via a similar cable.
translated, but I could only figure that out.
Because a splice point is named after the direction the speedometer indicates.

A wiring diagram for the control unit would be helpful.
I couldn't find anything like that in this forum.

Maybe one of you has something like that.



Best regards, Franz.

So, if you want to take the speedometer from the convertible, it might be a tight fit.

As long as the engine control unit (ECU) is not processing the speed signal for the speedometer, it will not be possible to obtain speed data from the original sensor.

The crankshaft pulley of the AHU (I'm not even sure if that's the basis of your conversion ) has a 4-0 crankshaft pulley. For the PD engines, you'll find a 60-2-2.
Therefore, when the sensor is accessed in parallel, the speed signal will not be correct.

And even that shouldn't be a problem, as long as the speed signal is not yet coming from wheel sensors, but from a sensor on the transmission; in that case, a splicing would be the solution.

What does the wheel speed have to do with the tachometer ?


Best regards, Jochen.

Jochen_145 wrote:

What does the wheel speed have to do with the tachometer ?

Yes, sorry, I was fixated on "Tacho".