Racelogic TC setup

[Exidous]

Glad to hear it!

The idea is the resistor acts as a load the noise cannot overpower but the sensor can.

[Gunnytron]

I am getting fu$&ed off with this now.

Spent hours yesterday rewiring all the resistors in, fired it up today and I only get a reading from one wheel speed sensor, the same one I had yesterday. Turn the car off then on again, I get no readings from any sensors.

...and the ABS light is back on again.

[Exidous]

Does the traction control connect to the sensors with one wire or two?

[Gunnytron]

Does the traction control connect to the sensors with one wire or two?

One wire, and from what I understand, and looking at the diagram, it doesn't matter which wire I tap into.

[Exidous]

It doesn't. The sensor outputs AC voltage. Voltage and frequency increase with speed and is present on both wires just 180° out of phase. Phase doesn't matter here.

You can try to move the resistor to the wire to the input of the RaceLogic and ground. This will help the ABS get a stronger signal and reduce noise to the TC...in theory.

[Gunnytron]

Like this?
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[Exidous]

Yes

[Gunnytron]

Alas exact same result. ABS light on and no signal from any wheels.

Looks like having the signal wire and the sensor wire is the only way to keep the ABS light off.

I think I am going to get a new length of shielded cable and just try wiring up one sensor. Although I have continuity from the TC connector all the way through to the ABS ECU pins, the wire is very thin and has fractured a few times when I've been messing with it.

[Exidous]

What do you mean be signal AND sensor wire?

[Gunnytron]

What do you mean be signal AND sensor wire?

I just mean inline on the sensor wire that goes to the TC unit, as I had it originally.

[Gunnytron]

I got a some new screened cable and connected just one sensor (front left). I disconnected /unsoldered all the other wires so that I was just dealing with one wire essentially.

First thing I did was look at the abs light. That came on when the sensor wire was connected so I fitted the 10k resistor. That made the light go out.

I ran the data monitor and got 0 wheel speed (manually turned the wheel). So I soldered in a second resistor running between the pair of sensor wires. Same result. I then removed that resistor and swapped the signal wire to the second sensor wire, same thing, nothing in the data monitor.

So, I am back where I started.

Maybe I will try attaching the sensor wire to the wheel speed sensor at the connector in the engine bay.

Also, can anyone confirm if you actually need to have the engine running for the data log to read the wheel speed sensors. You only need to have the ignition on right???

[Exidous]

The engine doesn't need to be running. The abs wheel should provide adequate voltage after only a couple MPH.

[Gunnytron]

Well I think it's time to give up. I tried every combination of wiring discussed in this thread but at the wheel speed sensor plug in the engine bay and I get nothing.

The only thing I do know out of all this is that the 10k resistor does prevent the ABS light coming on.

[Exidous]

When you spin the wheel do you get voltage across the two wires? Should be AC with only a couple volts at low speed. Did you also ohm out the sensor to make sure they are good?

[Gunnytron]

When you spin the wheel do you get voltage across the two wires? Should be AC with only a couple volts at low speed. Did you also ohm out the sensor to make sure they are good?

Yep, getting a millivolts reading when I spin the wheel.

I measured the resistance (with everything setup as in pic) and I got 239 on the white wire and basically nothing on the black. When I unplugged the sensor wire that goes to the TC unit the resistance at the white wire dropped to 0.737.

Here is one way I was testing it. I tried it on all 4 sensor pins at the TC plug. This also causes the ABS light to be lit. I also tried an alternative earth, just in case.

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