EFIDynoTuning Forum

Can this strategy be configured to use the VSS signal from a digital speedometer?

From the manufacturer: The speedometer signal output terminal (VSS) produces a +5 volt DC Square wave signal. This signal may be able to be used as a VSS signal with some OEM and aftermarket ECM’s and cruise control units.

Currently planning to complete pre-tune checklist then become premium member.

Im not sure if it has the hardware but you can try

I would rather go with something known to work if possible.
I have a Ford VSS that would goto pin 3 & 6 on a EEC-IV, but notice the pinout only shows one VSS+ pin on 68.
would the VSS- just goto ground and is this known to work? If not do you know what my options are?

there should be a vss- as well

Even if it didnt work its not a big deal.

What do you need vss for?

I guess that should have been my first question.

With no OSS, using manual transmissions NV3550 / Dana 20 do I need the VSS?

its not necessary its nice for dashpot decay being held on decel but not required

Further web reading suggests that pin 68 is a vss output signal after the PCM calculates MPH that is used for speedometer and cruise control (8,000 ppm). Sounds like the OSS input would be the only way to get a signal to the computer but VSS vs OSS pulse rate is significantly different.

looks like the explorer & ranger ECU has a 8000 ppm input on pin 58, fed by GEM but can be fed by only 1 wire of the vss.

that is only partially correct
pin 68 is a vss OUTPUT on some ecus that use a vss output which most do not

your not looking for an out though your looking for an input

pins 33 and 58 are vss but they arent used on the luxury ecus. You can wire it up and theres a 50/50 chance of it working as the hardware may or may not be there.

However you can set the aice chip for the oss input to be vss and you can probably get that reading for ease.

Regardless in all ecus the pulse count is adjustable.