TimH wrote:Maybe the notes on my schedule (from Ryan) are incorrect when they say RR and RL (they are only brought out to the expansion connector, not to the vehicle loom) as what you say (obviously!) makes sense.
I believe an external box is needed for the wheel speeds and I thought (again, perhaps erroneously) that this was only for two of the inputs: not sure why they would need different treatments though so maybe all the ABS sensors need the box...there are 2x AU, 2x AR and 2x AB inputs brought out to the expansion connector. Maybe the sensors *have* to use AB inputs so as not to upset the ABS system itself?
Would like to understand this, as our own prototype I/O expander is configured for AU-type inputs not AB (although it can be manufactured/modified to have AB type inputs).
The external box being referred to, is simply a VR - digital signal convertor, and the yellow one mentioned has been discussed here and is a yellow "relay" visually, and fitted to a few Vauxhalls. Not a relay as such, but it looks like a normal relay.
If wanting to use VR ABS signal for both ABS and ecu, something like that may be needed as attaching other wires directly to the sensor can throw a wobbler with the ABS ecu as it may think there is a fault.
Not sure if that varies depending on which ecu input you were to use though, with internal pullups off it might be ok.
I use the GT101 hall sensor for my wheel speeds, as an NPN sensor pulling to ground, on AU, AV and I think AR, no issues there. I had to use one on an AB input though and as such needed to pull that input to 5v with a pullup resistor in order that the sensor could then pull it to ground when active.
If the ABS signals are hall/digital, dont imagine attaching the signal wire to the ecu should cause it any problems with the ABS ecu ?