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Discussion Starter · #1 ·
Trying to tap into throttle body sensor and connect to AIM dash for throttle position data acquisition.
Does anybody know which wires I need to tap into?
Also, do I need to add a resistor?
1276842
 

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There would appear to be two throttle position sensors, pin 6 and pin 4. Might be either of them, but I would try pin 6, TPS1. Or, better yet, put a meter on both of them, ignition switch on, motor off, check the voltage on them as you step on the gas pedal. Pick the one that looks best across all the positions.

Here's the guts of one from a 1zr:
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I can't see as your 2zz would be any different. Pins look to be the same. The 2 sensors look to be in parallel.
 

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Discussion Starter · #3 ·
Ok... now I'm confused...
Looked up diagram again there's Throttle Pedal vs Throttle Body (first pic I posted)..
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Which would give better data, throttle position sensor or pedal position sensor?
 

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The throttle pedal has to sensors for redundancy. This way the ECU can fault and shutdown incase of a bad input; ie, runaway motor!

You will want to tap into the center point of pots which is either 279 or 282. If you had a Black Dash ECU, this information is available on the CAN bus.

Later,
Eldon
 

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The throttle has two signals that add to 5V: 1st increases from .5v-4.5v and the 2nd decreases from 4.5v to 0.5v. The upper and lower limits are approximate. For the pedal, the second pot is usually half of the first. No idea why there are two different conventions, and an automaker is always free to break convention randomly, but these are what's typically done.
 

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Discussion Starter · #6 ·
The throttle pedal has to sensors for redundancy. This way the ECU can fault and shutdown incase of a bad input; ie, runaway motor!

You will want to tap into the center point of pots which is either 279 or 282. If you had a Black Dash ECU, this information is available on the CAN bus.

Later,
Eldon
Unfortunately, I have white dash car FML.
So you recommend tapping into Throttle Pedal sensors/PPS not Throttle Body/TPS?
 

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Discussion Starter · #7 ·
The throttle has two signals that add to 5V: 1st increases from .5v-4.5v and the 2nd decreases from 4.5v to 0.5v. The upper and lower limits are approximate. For the pedal, the second pot is usually half of the first. No idea why there are two different conventions, and an automaker is always free to break convention randomly, but these are what's typically done.
Yes that's why I was going to use the throttle body/TPS to check voltage and configure in RS3.
 

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Unfortunately, I have white dash car FML.
So you recommend tapping into Throttle Pedal sensors/PPS not Throttle Body/TPS?
Honestly, you should do both because the ECU has a curve that correlates the PPS to the TPS. They are not 1:1.
Later,
Eldon
 

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The throttle has two signals that add to 5V: 1st increases from .5v-4.5v and the 2nd decreases from 4.5v to 0.5v. The upper and lower limits are approximate. For the pedal, the second pot is usually half of the first. No idea why there are two different conventions, and an automaker is always free to break convention randomly, but these are what's typically done.
That is interesting because according to the wire diagram above, that is not how they are wired. It would make sense for failure detection to have them work that way. That way if you lost power or ground, this would also be detectable.
Later,
Eldon
 

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That is interesting because according to the wire diagram above, that is not how they are wired. It would make sense for failure detection to have them work that way. That way if you lost power or ground, this would also be detectable.
Later,
Eldon
Everything I dealt with was Bosch, so it is also possible that other suppliers have different convention. Since I have an '05, I don't know who supplied the '06+ hardware. Looking at the service manual, it does say that the redundant sensors (for both the pedal and throttle) "should match within a defined tolerance" which aligns with the schematics above and with what you said. Either way, the first signal is always going to be the one to use and the second is where the different logic comes into play.
 

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Unfortunately, I have white dash car FML.
So you recommend tapping into Throttle Pedal sensors/PPS not Throttle Body/TPS?
I'd log both - looking at the PPS tells you what you asked and when, looking at the TPS is what the ECU gave you. For things like "Am I getting on the throttle too early?", it is helpful to know if there's a delay from the ECU or if it isn't going WOT when you hoped it was. Or maybe it was when you hoped it wasn't. Lotus isn't nearly as sluggish with their DBW as some others, but it still isn't a cable.
 

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Discussion Starter · #12 ·
Thank you all for posting.
I will try both TPS and PPS and see which data is more usable..

On to the next question... anyone has experience in assembling AIM 712 metallic Binder?

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Do I tap only the signal pins on the sensors or all signal, gnd, vbatt?
What is V reference 5V source be on the diagram?
 

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You only need to use Pins 1 & 2 for what you are trying to do. Vbattery and Vreference are for supplying a small amount of power to a sensor.
Later,
Eldon
 

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Discussion Starter · #14 ·
You only need to use Pins 1 & 2 for what you are trying to do. Vbattery and Vreference are for supplying a small amount of power to a sensor.
Later,
Eldon
Thank you eldonz!
I will tap sig and gnd for Pin 1&2.
one last question, you said "You will want to tap into the center point of pots which is either 279 or 282," above, since both are signal, but only one analog pin on the AIM binder, which or how should I connect them?
 

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If you do this do a very high quality job with proper tools, if you are going to use parts store crimps and tools dont bother IMO.
 

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Discussion Starter · #17 ·
If you do this do a very high quality job with proper tools, if you are going to use parts store crimps and tools dont bother IMO.
I was going to strip the wires from the sensor and add 18/20g TXL wires using U shape ring terminal crimp and solder to AIM binder connector and cover everything with adhesive lined heat shrinks.

What kind of crimp and tools would you consider as proper tools?
I'd appreciate for any recommendations and tips on how you would do it.
 

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I was going to strip the wires from the sensor and add 18/20g TXL wires using U shape ring terminal crimp and solder to AIM binder connector and cover everything with adhesive lined heat shrinks.

What kind of crimp and tools would you consider as proper tools?
I'd appreciate for any recommendations and tips on how you would do it.
What Kevin is cautioning against is making/creating a poor connection. If you are going to cut the wires to splice in, do not assume that a crimp is going to provide a "Good" connection. What I would suggest is to strip the insulation back and bare a section of wire. Wrap your new wire around the bare wire and solder. Then wrap the joint with something to protect it against the elements.

Now, if you had the tools and supplies, you could use Autosport connectors to splice into the harness and create another connection. If you went this way, you would spend over $100 dollars on connectors, $24 on the connector boots and if you don't have the crimp tool, another $250.

When I wired my data system into my car, I spent over $500 dollars just on the Autosport connectors! ;-)

Later,
Eldon
 

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Proper tools would be the cheap stuff you can get from racespec for example. My best luck has been with the raychem closed barrel splices and their yellow handled crimping tool, then as you said proper heat shrink back over things
 

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Wow, I didnt remember this tool being so much $$!

Tool

Splices (various sizes)

Proper Heat shrink.

If I was making an order from them i would get some DTM plugs so I could make everything replaceable, to use those you just need one cheap amazon tool.
https://www.amazon.com/Tool-Aid-188...ords=18890&qid=1609365739&s=automotive&sr=1-1 (not prime)

Or the whole set that most people get for starting home wiring:

I've yet to have anything crimped by these methods fail on my current build, and I have had things fail that were not done this way (larger crimps where I used a giant amazon crimper, or where I forced the issue and used too large of a barrel).
 
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