Vauxhall speed transducer - where am I going wrong

[kevw]

Hi all,

I have a RT Dash 2 that I am using with a Vauxhall 2.0 16V XE motor with an F20 gearbox.

I am having problems using the original Vauxhall speed transducer with the Dash 2. I have verified the transducer is wired correctly and working by hooking it up to a Vauxhall dashboard and the speed reading works correctly.

The transducer has the usual 3 wires, +12v, earth, signal. from research the transducer is a 16 pulse type.

I have also tried connecting the +12v to the 5v reference output of the Dash 2 with no success.

The dash 2 does not seem to acknowledge a reading at all when the transducer is connected.

Any help with this will be geatly received.

Regards

Kevin.

[stevieturbo]

Im using a GT101 hall sensor, which also supplies my ecu with a speed reference.

It's one of the few aspects of the Dash2 Ive got working properly !!!

My ecu provides +5v and ground, and I paired signal to ecu, and Dash2.

Dont forget to set the Dash2 to read from its own speed input, as opposed to RS232, using the config buttons.

[kevw]

Hi Steve,

Thanks for your reply, I believe the GT101 is a wheel speed sensor? i would like to try and use the standard vauxhall gearbox speed transducer if possible, I just don't know why it is not working with the Dash2!

I understand the Dash 2 requires a square wave input but I'm not sure if that's what the Vauxhall transducer is outputting or if that's the problem.

Dont forget to set the Dash2 to read from its own speed input, as opposed to RS232, using the config buttons.

I've checked this and it seems to be set correctly!

Thanks

Kevin.

[stevieturbo]

GT101 is just a hall sensor. Could be used for any such reference really.

No idea of its output though, or the factory speedo one you refer to.

I just know its one of the few bits that do work right for me lol

[faraday]

GT means gear tooth, but given the complexity mounting one in an automotive gearbox that hasn't been designed from scratch for such a thing, it would be easier to mount them on individual wheels.
This should be what you're trying to measure anyway.
The other problem you may well have, if you where trying to measure gearbox output shaft speed, with R-T hardware/GT101 sensing teeth is pulse frequency... too many teeth at high rpm.

[kevw]

Thanks for your help guys but as per my posts I did not want to mount another sensor. My question was about using the original Vauxhall transducer.

For reference, I have sorted this, I just needed to fit a 1k pull up resistor the same as you do with a GT101.

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