VSS and Transmission Output speed

[Peter D. Hipson]

For equal speeds (third and fourth gear) ratio between TOSS to TISS is 1043
(TOSS) to 1194 (TISS) giving a ratio of 1.14.  

TOSS and TISS can get up to voltages of about 12 to 15 VAC, if open
circuited. If in the TCM circuit then the values will (probably, I've not
measured 'em) be lower. GM states a given voltage at a given speed, figure
that the voltage while in operation will range from 4 to 12 VAC typically.

At 01:40 PM 3/12/99 -0500, you wrote:
>Peter D. Hipson wrote:
>> 
>> I'm doing extensive work on the TISS/TOSS senders. No, they are not equal
>> in pulses per revolution, there is a substantial difference. (I've the
>> ratios, if that's important...)
>
>Sure, pass 'em along for posterity's sake.
>
>> The senders are both magnetic coil type,
>> returning an A/C signal who's frequency (and voltage) varies with the RPM.
>> The only reason the voltage changes is due to improved efficiency at higher
>> speeds--the voltage change is not significant to the TCM, for example. Be
>> aware that common mode noise can be a problem with these senders, as can
>> bad connectors. As well, the sender itself fails frequently--arrggg! <g>
>> 
>I think I remember reading or hearing that the VSS signal voltage can
>get extremely high before conditioning.  What voltage levels are you
>seeing on average and how high do they peak?
>Shannen 
>

Thanks, 
        Peter Hipson (founder, NEHOG)
        1995 White NA Hummer Wagon