Terminal B is the ground wire terminal. Continuity to ground with the TPS mounted is incidental.
Well you should just get 1 or infinite. Until the throttle is opened slightly, then full contact Zero ohms
Green wire at check connector should have Zero resistance with Terminal A not B wire of haness. But harness measurments should be done with the ECU and TPS connectors unplugged, otherwise you could be measureing resistance of the ciruits inside ECU.
you should not be getting Negative Resistance values. 1 means infinite resitance, or a total open circuit, no conductivity. -1 means the meter is tring to read a resistance that is off the scale. You should set your Ohm meter to a higher scale like 10 or 20k ohms. The values you are trying to read are between 1k ohm and 10k ohms.
Are you testing it with the connector unplugged? Here's what it shuold be. Testing TPS itself, not plugged in.
Restistance between A(idle) and (ground) should be Infinite at throttle open, 0 or near zero (.1 ohm or less) at throttle closed.
Resistance between B(ground) and D(+V) changes with throttle opening between 3.5 to 6.5K Ohms
Resistance between B and C(signal V) changes with throttle opening. Less than 1K Ohm at closed, Greater than 2.4K ohms with valve fully opened(80% of resistance between B and D) Restistance should increase and decrease continuosly and smoothly between B and C.
"Resistance between B(ground) and D(+V) changes with throttle opening between 3.5 to 6.5K Ohms"
Is this correct? This part of the test procedure that says there should be variable resistance between B and D?
I am having a off-idle hesitation and getting a TPS code. I have 4 TPS and all of them show about 4.5 ohms resistance between B and D and that value is unchanged with opening and closing of the throttle. The unlikely odds that I have 4, similarly failed TPS makes me want to confirm. Aside from that, all 4 of my TPS test Ok In all other parts of the procedure.
1992 SPFI Loyale. 170k miles.
Edited by markjw, 25 January 2013 - 12:13 PM.