TCMUX & M800

[killerbee]

I have searched the previous posts and didn't find anything completely answering my question(s). I have an M800 and am considering using traction control. However, I am not too clear on how to achieve this.

It would seem that all I need to do is use the 4 digital inputs configured as wheel speed sensors (in Hall format using mag converters). In the m800 sw (V3.5) adjust -> sensor setup -> input setup -> pin assignments -> speed in the default channels are LD, RD, LG & RG. Is this all that is required ? The only down side of this is that you use all of your 4 dig inputs.

The other option seems to use the TCMUX. According to the catalog: The traction control multiplexer takes 4 individual wheel speed signals, and turns them into one coded signal for an ECU to read as driven speed (wheels that have power), undriven speed (rolling wheels) and slip (% difference between driven and undriven wheels.) In the M800 s/w there are 3 parameters TCM Rolling, TCM Ldrive and TCM Rdrive. What pin is the output of the TCM assigned to (dwg A01 only makes reference to the M4 and M8 ECUs, if I had to guess I'd say B8)

Will either of these approaches work ?

[MarkMc]

Hello,
You don't neccessarily need all four wheel speeds, you can get away with one on the front and one on the back (let's assume rear wheel drive). Four wheel speeds just means you can calculate a balance across each end of the car, e.g. if you are going around a corner the ECU picks the fastest of the two front wheels, e.g.2 on the rear the ECU can calculate a biased average of the two. Just makes it a little more refined.

If you had a locked differential then the two driven wheel speeds must always be the same so you would not need to waste a digital input.

The TC Mux can take four wheel speeds and outputs the coded signal to one digital input (saving you three on the ECU).

Either approach is fine and will give the same result.