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Variation in TPS each time I look

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Old 04-19-2014, 07:17 PM
  #21  
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No offense Mike, but I don't have a car sitting in front of me to look at to know which is top or bottom. I gave you a screenshot of the wiring diagram that shows a picture of the connector (with positions) and even gave you the colors.

That said, I think we are 99% sure that you are getting 5v to the TPS.

What is interesting though is the .5v that you are getting on the top wire.


According to that, the wire you are getting .5v from SHOULD be a ground. Instead of metering voltage, check resistance to ground. I am guessing this has something to do with your problem.
Attached Thumbnails Variation in TPS each time I look-screen-shot-2014-04-19-6.15.50-pm.jpg  
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Old 04-19-2014, 09:13 PM
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I will double check in the morning when I have better light but those are different colors than I have. It looks like mine are B/LG = 5v, B/R = Ground, G/B = .5v

I will verify everything tomorrow to be sure. But I wired the VRef to the B/LG, Ground to B/R and TP Signal to G/B

Thank you for your help (sorry, I was out to dinner earlier)
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Old 04-19-2014, 09:23 PM
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you wired it wrong.

b/lg is always a sensor ground.
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Old 04-20-2014, 12:10 AM
  #24  
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You sure brain? That's not the way it looks in the wiring diagram.

B/R = Black with Red stripe = sensor ground
G/B = Green with Black stripe = signal
LG/R = Light-Green with Red stripe = vref

I am confused though because black/light green doesn't show up as a throttle related wire. Mind you, my wiring diagrams aren't for a 2003 but I have one for both a 2000 and a 2001 and they both agree with the colors and signals I posted here.

EDIT:

Rather than argue about it I just went outside and metered my own.


My wires meter out as:
B/R = Black with Red stripe = sensor ground (ground)
G/B = Green with Black stripe = signal (happens to be just under 5v at the moment for some reason)
LG/R = Light-Green with Red stripe = vref (5v)
Attached Thumbnails Variation in TPS each time I look-throttle_plug.jpeg  

Last edited by Chiburbian; 04-20-2014 at 12:28 AM.
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Old 04-20-2014, 12:35 AM
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Old 04-20-2014, 07:16 AM
  #26  
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I will try swapping the outer wires first as I am confident that the middle is ground.

May not be able to do it today as it is my wife's birthday so she is priority today.
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Old 04-20-2014, 07:37 AM
  #27  
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So far so good. I ran downstairs while she is asleep and reversed the wires. It is much more stable (although the adc numbers are very high, 700+).

I can't check out the TPS with the car started yet because it will wake her :-)

I really do appreciate everyone's help as always

Variation in TPS each time I look-forumrunner_20140420_073730.png
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Old 04-20-2014, 08:37 AM
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okay, sorry B/LG is different than G/B.
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Old 04-20-2014, 09:50 AM
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That's not what confused me Brain.

I was trying to fugure out if you had a typo and you meant LG/R or if you meant G/B. Either way, my references had neither of them as sensor ground.
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Old 04-20-2014, 09:54 AM
  #30  
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I reversed the outer 2 wires and all is great now!

Thanks for all the help. I learn something new every day
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Old 04-20-2014, 10:08 AM
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Originally Posted by Chiburbian
Either way, my references had neither of them as sensor ground.
I wasn't looking to be honest. All 90-97s use b/lg as a sensor ground wire and that went out the window in 99. so when I saw the reference to that I was like well there's an issue.

Looks like I was still correct about the wiring issue, lol.

Last edited by Braineack; 04-21-2014 at 08:15 AM.
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Old 04-20-2014, 10:53 AM
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Ahh, ok that makes sense. I wonder when they made that change. (Seems strange to do it after a year of NBs with no other major changes)
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Old 08-12-2014, 07:16 AM
  #33  
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Just to follow up...I sent the MS to Peter Florance at PFTuning to check my soldering.Turned out that I had a bad joint at R9. He fixed that and now the TPS is stable and where it should be.

Thanks to everyone for your help
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