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  #1  
Old 04-24-2006, 06:45 PM
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Testing the TPS

As a result of another thread involving a faulty throttle position sensor, a possible handy man method of reliable fault finding has come to mind, but experimentation is required.

As many will be aware the TPS comprises a potentiometer consisting off a conductive plastic resistive element around which traverses a wiping contact. Dirt on the surface can interrupt contact, as can a faulty element or inadequate pressure on the contact. It can be difficult to detect intermittent contact as the wiper is turned, due there being little time to register a measurement as the wiper passes over a faulty area. The response time of a typical ohmmeter or voltmeter is inadequate. A meter with a bar graph or an oscilloscope is required. The handyman does not normally have access to this sort of gear.

Most will have been annoyed by audio gear which has a noisy volume control. Has the penny dropped ?????!!!!!

Hook up the TPS with a capacitor of a few mfds in series with a torch cell and stick the output across the input of an audio amplifier. There are three connections to the TPS, which appears to used in a voltage divider configeration. Terminals 1 and 3, (4k 0hms) should be connected across the amp. input and 1 and 2 or 2 and 3, to the capacitor in series with the torch cell. Anything will do, guitar amp, walkman add on, whatever. In fact high impedance headphones should work. Turn the TPS and listen to the music ?! A nice rushing sound as the unit is turned will be good music. Nasty static will be bad news.

This is simply an idea at this stage and requires experiment by a keen member who has a TPS on hand. I feel that the effort would be worthwhile. Any takers ?.
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Last edited by Trevor; 04-24-2006 at 09:45 PM. Reason: Sentence added.
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  #2  
Old 04-25-2006, 08:36 PM
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spinn360 spinn360 is offline
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Wink I dont wanna

maybe someone other then me will do it. I just checked mine with the voltometer on ohms and slowly ran it up to5.0 from 0.0 or 1.0 (cant remember)anyways I think there is actually a write up of how to check the TPS in the how to somewhere. After I cleaned it it moved smoothly up and down, no jumping which might trick the TCU into thinking the gas was suddenly, and quickly moving, and turning on the power mode.
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  #3  
Old 04-25-2006, 09:09 PM
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Quote:
Originally Posted by spinn360
maybe someone other then me will do it. I just checked mine with the voltometer on ohms and slowly ran it up to5.0 from 0.0 or 1.0 (cant remember)anyways I think there is actually a write up of how to check the TPS in the how to somewhere. After I cleaned it it moved smoothly up and down, no jumping which might trick the TCU into thinking the gas was suddenly, and quickly moving, and turning on the power mode.
There is data in the how to section, which as it happens, I wrote. As explained a votmeter, ammeter or ohmeter, will not provide absolute indications of a fault, even though a worthwhile rough check can be made. What I have now suggested would be a far superior method.
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  #4  
Old 04-25-2006, 09:45 PM
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I still dont wanna so poo!
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  #5  
Old 04-26-2006, 03:48 AM
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Quote:
Originally Posted by spinn360
I still dont wanna so poo!
I get the picture. Poo to your intermittent problem. *<[
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  #6  
Old 04-28-2006, 04:38 PM
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Quote:
Originally Posted by Trevor
As a result of another thread involving a faulty throttle position sensor, a possible handy man method of reliable fault finding has come to mind, but experimentation is required.

As many will be aware the TPS comprises a potentiometer consisting off a conductive plastic resistive element around which traverses a wiping contact. Dirt on the surface can interrupt contact, as can a faulty element or inadequate pressure on the contact. It can be difficult to detect intermittent contact as the wiper is turned, due there being little time to register a measurement as the wiper passes over a faulty area. The response time of a typical ohmmeter or voltmeter is inadequate. A meter with a bar graph or an oscilloscope is required. The handyman does not normally have access to this sort of gear.

Most will have been annoyed by audio gear which has a noisy volume control. Has the penny dropped ?????!!!!!

Hook up the TPS with a capacitor of a few mfds in series with a torch cell and stick the output across the input of an audio amplifier. There are three connections to the TPS, which appears to used in a voltage divider configeration. Terminals 1 and 3, (4k 0hms) should be connected across the amp. input and 1 and 2 or 2 and 3, to the capacitor in series with the torch cell. Anything will do, guitar amp, walkman add on, whatever. In fact high impedance headphones should work. Turn the TPS and listen to the music ?! A nice rushing sound as the unit is turned will be good music. Nasty static will be bad news.

This is simply an idea at this stage and requires experiment by a keen member who has a TPS on hand. I feel that the effort would be worthwhile. Any takers ?.
I guess that I must now presume that my penny has simply dropped into cyberspace !
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As a child, on cold mornings I gladly stood in cowpats to warm my bare feet, but I detest bull$hit!

Last edited by Trevor; 04-28-2006 at 04:42 PM. Reason: Error
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  #7  
Old 04-28-2006, 05:40 PM
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Quote:
Originally Posted by Trevor
As a result of another thread involving a faulty throttle position sensor, a possible handy man method of reliable fault finding has come to mind, but experimentation is required.

As many will be aware the TPS comprises a potentiometer consisting off a conductive plastic resistive element around which traverses a wiping contact. Dirt on the surface can interrupt contact, as can a faulty element or inadequate pressure on the contact. It can be difficult to detect intermittent contact as the wiper is turned, due there being little time to register a measurement as the wiper passes over a faulty area. The response time of a typical ohmmeter or voltmeter is inadequate. A meter with a bar graph or an oscilloscope is required. The handyman does not normally have access to this sort of gear.

Most will have been annoyed by audio gear which has a noisy volume control. Has the penny dropped ?????!!!!!

Hook up the TPS with a capacitor of a few mfds in series with a torch cell and stick the output across the input of an audio amplifier. There are three connections to the TPS, which appears to used in a voltage divider configeration. Terminals 1 and 3, (4k 0hms) should be connected across the amp. input and 1 and 2 or 2 and 3, to the capacitor in series with the torch cell. Anything will do, guitar amp, walkman add on, whatever. In fact high impedance headphones should work. Turn the TPS and listen to the music ?! A nice rushing sound as the unit is turned will be good music. Nasty static will be bad news.

This is simply an idea at this stage and requires experiment by a keen member who has a TPS on hand. I feel that the effort would be worthwhile. Any takers ?.
Trevor to USA translation:
torch cell = Flashlight Battery

Would you suggest 1.5 volt, 6 volt, 12 volt? Do we need to be concerned about the voltage path, Positive vs. Negative?

Dan
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  #8  
Old 04-28-2006, 05:56 PM
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cyber cyber cyber space hello hello
is is anyone one out there there?

I may do it, but I am not in any hurry as I dont believe this is my problem but seeing as how I have an extra one I might do it when I get some free time. Are you happy now?
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  #9  
Old 04-28-2006, 09:14 PM
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Quote:
Originally Posted by spinn360
cyber cyber cyber space hello hello
is is anyone one out there there?

I may do it, but I am not in any hurry as I dont believe this is my problem but seeing as how I have an extra one I might do it when I get some free time. Are you happy now?
The message was directed to all and sundry and most certainly not personally to you. It has nothing to do with your problem and was posted as being of general interest. The intent was to prevent the post from being missed by someone who could benefit.

Why the nasty sarcasm ?
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  #10  
Old 04-30-2006, 04:16 PM
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Its only sarcastic if you read it that way. I was trying to be funny I guess I failed I should have posted one of these next time I will!

And I know you werent posting directly to me. even though the world does revolve around me. I know I know I was just throwing in my own personal information, as I knew that you would know what I was talking about. And I dont believe Poo is a cuss word. I believe you and I are from two different worlds trevor, or at least two different sides of the same one!
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Last edited by spinn360; 04-30-2006 at 04:19 PM.
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  #11  
Old 04-30-2006, 04:58 PM
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Quote:
Originally Posted by spinn360
Its only sarcastic if you read it that way. I was trying to be funny I guess I failed I should have posted one of these next time I will!

And I know you werent posting directly to me. even though the world does revolve around me. I know I know I was just throwing in my own personal information, as I knew that you would know what I was talking about. And I dont believe Poo is a cuss word. I believe you and I are from two different worlds trevor, or at least two different sides of the same one!
Your courtesy and reply is sincerely appreciated. Unfortunately the written word can be deceiving as you point out and unwittingly we became at cross purposes. Be sure I was not offended by "poo", as you may have observed I confirm having been closely involved with the stuff !!

Although we are on different sides of the world, I am sure we are both within the same one. Not a problem, not to worry and all is well.

Cheers, Trevor *<)
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  #12  
Old 04-30-2006, 09:31 PM
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Great alls well that ends well

If your all good, then I'm all good. Sorry for any mistaken communication.

Cheers - shawn
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  #13  
Old 04-30-2006, 10:15 PM
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Quote:
Originally Posted by intelisevil
Trevor to USA translation:
torch cell = Flashlight Battery

Would you suggest 1.5 volt, 6 volt, 12 volt? Do we need to be concerned about the voltage path, Positive vs. Negative?

Dan
"Torch cell" had me scratching my head.

A few good meters were out of my range when I went looking a couple weeks ago so this method sounds interesting.
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