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Old 06-24-2019, 11:33 PM   #253
06YarisRS
 
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Gauge Pod Test Fit

A bit of a spoiler. I won't have pics until tomorrow, but, the good news is... the pillar is a great fit. Is it 100% perfect? No, but it's very acceptable. The contours are very good and the fit should be fairly seamless. I will need to figure out a method of attachment as there are no pins. I think I'll use long screws, drill a couple holes in the steel pillar and pull the gauge pod cover tight. The way it's designed, I can hide the screws really well just under the top and bottom pod holes. The screws will be invisible from the driver's and passenger's positions. I plan to spray the pillar with a flat or satin clear coat. Right now, although the color is a close match, the pod is way too shiny, whereas the dash has more of a matte finish.

Pics tomorrow, I promise.
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Old 06-25-2019, 07:38 PM   #254
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Gauge mounting...turning point

I am heavily leaning toward not using the A-pillar gauge pod. One things I've always appreciated about the Yaris is it excellent visibility from the driver's seat. The gauge pod would look amazing in the car, without a doubt, but I just can't spare any visibility. It is not overly intrusive, but I could see the larger blind spot potentially causing a problem. I also like to drive with my seat all the way back. If I push the seat forward, visibility is fine. Again, a compromise I don't think I'm willing to make at this point. It's a bit of a shame, because with a few mods to the pillar and a little matte clear on it, it would look pretty darn good. For a cheap attempt at a gauge pod, they did a pretty good job fitment-wise.

So, some pics:

Pod test fit in my '08...



My alternative plan. I just spent a couple of hours shaping the gauge 'adapters' to fit the curve of the glove box. This was tedious and it turned out pretty good, but not perfect. I plan to drill 3 holes a bit smaller than the gauges and then use some kind of small saw or my dremel and sanding disk to round out he holes to size. I plan to do this on the car as I don't feel like taking the entire dashboard off. I happen to have have a spare dash - the one that originally came with my '06, so I used its driver's side glove box to shape the gauge adapters. I'll epoxy the gauge adapters to the dash from the inside.

Opinions sought... I can either line the gauges up in a straight row of follow the curve of the steering column bezel. The problem with the latter is that the gauge face angles would be off. so, it's probably best to keep them in a straight line.

Gauges in line:



Gauges following steering column bezel (well, sort of):




Other pics:





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Old 06-25-2019, 09:58 PM   #255
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A bit of progress on the gauges this evening...

I actually tired the gauges flush and liked it better, except that they don't sit level and you can notice this from different angles. I think I'll paint the gauge trim rings black. The silver is a bit stark and black would go better with the interior. The gauges have film over the glass (plastic?) and I'll remove them when they are all installed. Once nice thing I discovered is if I modify the hardware, I won't have to epoxy the gauge adapters to the glove box.











All three gauges in, but not wired yet

I decided to follow the contour of the streering column cover and I'm glad I did. For one, it looks better and visibillity of all gauges is perfect from my seating position. I think they look great, but if the silver rings are easy to get off, I might paint them black.



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Old 06-27-2019, 12:02 AM   #256
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F/IC Mounting and Wiring Started

I mounted the F/IC flat on the plastic tray behind the glove box by laying down a couple foam strips (used on old 6" compounding pad), drilled holes and ziptied it in. It's solidly mounted and no rattles.



Started wiring the F/IC. I just had a bit of time, so only got done the crankshaft sensor/F/IC/ECU connections. I hope to have all the wiring done in the next day or two. I'm now off for the summer, but have two kiddies to watch, so time is a bit limited.

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Old 06-27-2019, 01:13 PM   #257
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F/IC fuel injectors wired

Well, three of them anyway. It looks messy now, but it will be all tidied up, taped and tucked back into the plastic ECU wire retaining clip.

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Old 06-27-2019, 01:19 PM   #258
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This is the part you've been somewhat dreading, eh?
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Old 06-27-2019, 05:54 PM   #259
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Quote:
Originally Posted by ern-diz View Post
This is the part you've been somewhat dreading, eh?
It is somewhat, ern-diz. I'll be cringing as I reconnect the negative battery terminal. Lol. I could never get a definitive commitment from anyone that my wiring diagrams are correct. I am hoping that if there are no sparks and a no start scenario, that the ECU will at least set a code to point me in the right direction.

I finished the fuel injectors, power ground and the MAF wiring. Just TPS, signal ground and 12V power left to connect. Hoping for a start tomorrow. Wish me luck lol!
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Old 06-27-2019, 10:30 PM   #260
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Current state of wiring

So far I have hooked up: injectors, MAF, crank, +12V power, and 2 grounds. I am at a standstill until I figure out where to find a signal ground, as I can't figure it out from the diagrams. I'm also struggling with the the TPS+ connection.

Here is a pic of the current state. The wire in loom running across the top is the +12V switched power source which comes from the smaller ECU connector. The bunch of wires to the left will all bundle up nicely and fit into the ECU plastic connector cover. Everything will be enclosed in a large piece of conduit and taped really well. It should look completely factory when I'm done.

I have only 4 wires remaining to be hooked up: TPS+, 021+, 022+ and signal ground.



Next post will be an appeal for help from anyone familiar with Toyota wiring diagrams. I have an email in to AEM, but they don't want to make specific connection suggestions. I'll try the turbokits guys, and then maybe seek out an automotive wiring forum.
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Old 06-27-2019, 10:41 PM   #261
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Seeking wiring suggestions

As mentioned, I'm struggling with the last few wires for the F/IC install. I can't find anything online that shows a specific Toyota signal ground symbol. I'm also not sure which wire from the ECU to hook to the F/IC TPS+ wire. Please see diagrams below and if you know the answer(s), please shout them out.

Grounds?



Here is one of the pics/questions I sent to AEM.




EDIT: I found this site which leads me to believe that I should use the Yellow VTA wire. I'm open to interpretations.

http://www.tsienna.net/throttle_peda...quot_-542.html
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Old 06-28-2019, 09:34 AM   #262
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Temp guages bench test

I'm liking these gauges, though I wonder how long they will last. I'll be replacing much of the wire with true 18 AWG and soldering and heat shrinking all connections. Wire will all run through taped up conduit and attached along its length with zipties.

The gauges look much, much better in person than these pics depict. The colors are much brighter and deeper in person. Should look amazing in the car. The blue color is triggered by the headlight switch, so they run blue at night and white during the day.

As for accuracy, the two gauges climb at very slightly different rates but usually stop at the same position. I used two candy thermometers - which were close to each other, but not perfect. I averaged the candy thermometer readings and used that to compare to the gauges and the readings were very close. My best guess would be 3 - 4 degress different than the candy thermometer average. Not a scientific approach, but the best I can do given what I have. I'd like to test the oil pressure gauge, but that would take to much frigging to connect to my compressor to test that.

Kudos to Prosport for at least having consistency in their gauges and sensors. I had a couple Autometer (mid range quality) temp dial gauges years back and they were off quite a bit more from each other than these gauges are.



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Old 06-28-2019, 09:37 AM   #263
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TPS usually means Throttle Position Sensor. In a mechanically connected throttle, there is a rheostat (dimmer) connected to the shaft of the throttle valve so that other systems know what position the valve is in. In drive-by-wire systems (which almost all modern vehicles are) the position is sent by a Hall-effect sensor, not a rheostat. I'm having a hard time finding if the AEM can use that as an input.

Here's a simple diagram from a Corolla repair manual that uses a rheostat: http://www.tcorolla.net/circuit_description-558.html

Here's a very detailed technical report that discusses the connector and what the wires are on the 2ZR (or equivalent) ECU: https://web.archive.org/web/20140727...rticle_id=3597

Here's a technical writeup from an unintended acceleration investigation that uses different naming conventions: http://www.safetyresearch.net/Librar...port022110.pdf

Bottom line is, I don't know how to connect a Hall-effect sensor to an AEM EMS. My google-fu isn't turning up any obvious answers either. Hrm.
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Old 06-28-2019, 09:40 AM   #264
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Looking at the link you posted, the 0-5V signals should be your TPS. VTA1 is the one that you want (VTA2 will be offset by a certain amount and will likely cause problems).
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Old 06-28-2019, 09:45 AM   #265
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For posterity, here's what the pins are:
  • M+ / M- are the servo control signals. It's the same thing that you use on RC vehicle servos--Pulse Width Modulation (PWM)--to command the servo to a specific position. It's shielded to prevent electrical interference with the signal.
  • VCTA is the DC power supply to the circuit
  • ETA is the DC ground/common
  • VTA1 is the throttle position feedback, 0-5 VDC. 0 is closed, 5 is WOT.
  • VTA2 is the monitor signal for VTA1, which allows the ECU to detect a failed or faulty signal from VTA.
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Old 06-28-2019, 10:05 AM   #266
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Sam. Thank you!!!! You are de man!

I'll have a read of what you linked.

I have a very big favour to ask if you're up for it. Could you endeavour to answer two questions for me if I were to send you my engine control wiring diagram?


1) I have attached the F/IC "switched 12V power to pin 1 (+B2) in ECU small connector A21. This traces back to the EFI relay. This is what I was advised to do, but no explicit directions were given other than take it off the EFI relay. Is this in fact a switched power source, or is this black wire always hot?

2) Does the triangle symbol leading to what looks like earth ground in the Toyota wiring diagrams mean it's a "signal ground"?

Thanks!

EDIT: In re-reading your post, I see that ETA is DC ground common. Is this a signal ground and could I attach the F/IC signal ground to ETA (Pin 91 on C19)? Also, above I reference (+B2) in connector C19, I meant connector A21.

Edit 2: I'll be speaking to my tuner today and asking him of I need the TPS hooked up at all as it may be that the car's ECU can handle that and the F/IC doesn't need to be involved.
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Old 06-28-2019, 01:49 PM   #267
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Plug Gapping

The plugs need to be gapped down from .044" to .028".

Removing coil packs



Removing plugs



Gapping plugs



Torquing to 20nm (177 in/lbs, 14.75 ft/lbs)

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Old 06-28-2019, 01:54 PM   #268
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I'll have to pull up the full EWD before I can solidly comment on the switched DC power, but that sounds reasonable.

Short answer, yes the triangle is ground.

Long answer is more complicated. You don't have to read this stuff, just some general theory and why there are different symbols.

The term "ground" is rather loose and fluid and causes no end of confusion--even to myself. The "E" in all of those connections probably refers to "earth", i.e. the planet, which is the standard zero reference for most voltage measurements. But in the case of your car, it's too insulated by the tires to be able to use that, so instead we use the negative terminal of the battery as zero. Connections direct to the Earth normally use the three shrinking lines. A local ground reference or "common" connection normally uses the downward triangle to differentiate it and in some cases may not be connected to the earth ground. There's also a "chassis" ground symbol that looks like a 3-tined rake. They are frequently used arbitrarily or will have different meanings in different international standards, leading to lots of confusion if you don't understand what the original intent was or what standard (if any!) it was drawn to.

If you get really technical, everything that conducts electricity has some resistance--even gold plated contacts and super pure copper wires. Good old Ohm figured out the relationship between resistance, voltage and current and his Law tells us that there is a voltage difference between any two points in a circuit that have resistance between them and a current flowing from one to the other. Generally speaking, anything connected directly to the battery with zero resistance is also at zero volts. Ideally you would be able to directly connect all of the ground wires to the battery terminal in a "star" configuration to minimize any voltage offsets. You can see in some wiring diagrams that multiple wires converge at a connection to ground, which is normally on the chassis. The wires and chassis all have some (very small) resistance in them, which creates a (very small) voltage difference between the ends of the wires or between the attachment point of the local ground and the nearest big wire on the negative terminal. That small bit of offset usually doesn't impact anything because it's effectively zero. If you have to take a very accurate measurement on that circuit, you should measure from the local ground point, not the battery. In the case of electrical signals or data communication, you need that reference point to be consistent and electrically "quiet". If you use a ground node near your injectors or the voltage regulator on your alternator you can inject lots of unwanted spikes or noise into your ground reference, messing up the relative voltage between that point and the supply/battery.

So the trick here is that you want as many of the ground references for the AEM and ECU to be as close as possible to minimize noise or offsets. In other words, choose wisely where you connect those wires.

Case in point: my horn doesn't work. The horn switch is fine, the relay is fine, the fuse isn't blown, and there's 12V at the positive terminal when the horn is pressed. It doesn't work because there is too much resistance or poor continuity between the horn's internal ground connection and the chassis. There's corrosion on the bolt threads between the horn and the battery as a result of taking the front bumper apart a few times and living in a state that salts their roads. My next step in fixing it will be to run a new ground wire from the nearest ground point to the horn itself and bypass the bad connections in between. If that doesn't work then I will run it to the battery directly. There's no risk of it causing a dangerous short though because the battery is on the other side of the relay contacts and there's a 10A fuse in that circuit as well. Some cars use the opposite method and put the horn on the battery side of the circuit and connect it to ground with the relay. That means the horn input is always "hot" and has the potential for a short to ground before the contacts, resulting in a horn that won't stop honking unless you pull the fuse or relay.
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Old 06-28-2019, 02:09 PM   #269
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Originally Posted by CrankyOldMan View Post
I'll have to pull up the full EWD before I can solidly comment on the switched DC power, but that sounds reasonable.

Short answer, yes the triangle is ground.

Long answer is more complicated. You don't have to read this stuff, just some general theory and why there are different symbols.

The term "ground" is rather loose and fluid and causes no end of confusion--even to myself. The "E" in all of those connections probably refers to "earth", i.e. the planet, which is the standard zero reference for most voltage measurements. But in the case of your car, it's too insulated by the tires to be able to use that, so instead we use the negative terminal of the battery as zero. Connections direct to the Earth normally use the three shrinking lines. A local ground reference or "common" connection normally uses the downward triangle to differentiate it and in some cases may not be connected to the earth ground. There's also a "chassis" ground symbol that looks like a 3-tined rake. They are frequently used arbitrarily or will have different meanings in different international standards, leading to lots of confusion if you don't understand what the original intent was or what standard (if any!) it was drawn to.

If you get really technical, everything that conducts electricity has some resistance--even gold plated contacts and super pure copper wires. Good old Ohm figured out the relationship between resistance, voltage and current and his Law tells us that there is a voltage difference between any two points in a circuit that have resistance between them and a current flowing from one to the other. Generally speaking, anything connected directly to the battery with zero resistance is also at zero volts. Ideally you would be able to directly connect all of the ground wires to the battery terminal in a "star" configuration to minimize any voltage offsets. You can see in some wiring diagrams that multiple wires converge at a connection to ground, which is normally on the chassis. The wires and chassis all have some (very small) resistance in them, which creates a (very small) voltage difference between the ends of the wires or between the attachment point of the local ground and the nearest big wire on the negative terminal. That small bit of offset usually doesn't impact anything because it's effectively zero. If you have to take a very accurate measurement on that circuit, you should measure from the local ground point, not the battery. In the case of electrical signals or data communication, you need that reference point to be consistent and electrically "quiet". If you use a ground node near your injectors or the voltage regulator on your alternator you can inject lots of unwanted spikes or noise into your ground reference, messing up the relative voltage between that point and the supply/battery.

So the trick here is that you want as many of the ground references for the AEM and ECU to be as close as possible to minimize noise or offsets. In other words, choose wisely where you connect those wires.

Case in point: my horn doesn't work. The horn switch is fine, the relay is fine, the fuse isn't blown, and there's 12V at the positive terminal when the horn is pressed. It doesn't work because there is too much resistance or poor continuity between the horn's internal ground connection and the chassis. There's corrosion on the bolt threads between the horn and the battery as a result of taking the front bumper apart a few times and living in a state that salts their roads. My next step in fixing it will be to run a new ground wire from the nearest ground point to the horn itself and bypass the bad connections in between. If that doesn't work then I will run it to the battery directly. There's no risk of it causing a dangerous short though because the battery is on the other side of the relay contacts and there's a 10A fuse in that circuit as well. Some cars use the opposite method and put the horn on the battery side of the circuit and connect it to ground with the relay. That means the horn input is always "hot" and has the potential for a short to ground before the contacts, resulting in a horn that won't stop honking unless you pull the fuse or relay.
Wow! Thanks Sam! If I'm understanding correctly, then grounding the "signal ground" from the F/IC at the battery would be ideal. However, would that long a run (probably about 3.5') pick up interference and cause faulty voltage readings? I could run the "signal ground" to the battery. I have tons of wire and conduit. Thoughts?

I have the Scion xD engine control diagrams if you don't. I'd be happy to send that to you if you wanted to let me know if my switched power is actually switched.

Thanks again!
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Old 06-28-2019, 04:36 PM   #270
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Quote:
Originally Posted by 06YarisRS View Post
Wow! Thanks Sam! If I'm understanding correctly, then grounding the "signal ground" from the F/IC at the battery would be ideal. However, would that long a run (probably about 3.5') pick up interference and cause faulty voltage readings? I could run the "signal ground" to the battery. I have tons of wire and conduit. Thoughts?

I have the Scion xD engine control diagrams if you don't. I'd be happy to send that to you if you wanted to let me know if my switched power is actually switched.

Thanks again!
In a perfect world, yes, but only if everything else in the vehicle was able to do that. There's probably a closer ground that's used by the ECU. You'd want to try and use that instead since you're connecting to that part of the electrical system. The other thing you risk doing by running a separate conductor back to the battery is called a ground loop. Basically you're making a new path for electrons to flow between the two ground reference points and causing one of them to be above zero. Here's an article with some examples of automotive grounds.

I should have a copy at home but might not have time to review it tonight.
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