2007 Avalon. Speedometer quit working, "ABS", "BRAKE", Check Engine" Lights

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I think you might want to re-read his post once more.

Just to add to clinebarger's post...

"The speed sensor detects the wheel speed and sends the appropriate signals to the skid control ECU. The skid control ECU converts these wheel speed signals into a 4-pulse signal and outputs it to the ECM via the combination meter. The ECM determines the vehicle speed based on the frequency of these pulse signals."


140567195
Whoops, wrong photo. I meant to attach this one:

1637252860172.jpeg
 

AlphaOmega

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Alright. Thanks for bearing with me! @The Critic, the "speed sensor" in the above photo, which one is it? So far I understand that there are 2 "speed sensors" that plug into transmission: NT (direct clutch) and NC (counter gear); and then there are 4 individual wheel speed sensors.

My understanding (please do correct me!) That wheel speed sensors are used to enable ABS/VSA functions by monitoring the difference between each wheel's speed and not to measure actual vehicle speed, am I wrong? Actual vehicle speed is measured though transmission, no?

I'm not arguing - I'm discussing, so that I could roll your @The Critic and @clinebarger logic onto my existing, primitive frame of reference and modify it accordingly!

*** There's picture I have found on the internet that does not show SKID Control ECU in the loop to determine/display vehicle speed. Are you able to confirm if my 2007 Avalon with a 5-speed auto falls under this scenario:
Screenshot_20211118-023556.png


OR your scenario:
1637252860172.jpeg
 
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I'd go to a junkyard and grab both sensors off a 5-speed toyota tranny. That way you'll get OE for cheap. Use your cell phone for cross referencing.

If these sensors are covered in metal shavings it might mean bad news for your tranny. What if you did a fluid drain and fill while you're waiting and messing around? Or pull your current sensors and see if they're clean.

If you have an old 32 bit windows XP- win 7 laptop you can get a knockoff version of the dealer Techstream software with OBD dongle for under $20 which will read every module as well, if this blue driver stops working for you, but it sounds like it's meeting your needs now.
 

AlphaOmega

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The 4 Wheel Speed Sensors are wired directly to the ABS/Skid Control Module, This Module takes the A/C Sine Wave Signals & Outputs D/C Square Wave Signal on a single wire.
This Signal is then sent to the Speedometer (Combination Meter), Then to the ECM which is the module that's outputting the P0500.

I would check for ABS Module wheel speed DTC's before continuing any further.

So I've ordered a used ABS module/pump combo with exact same numbering as the one on my car from eBay. Will I be able to transfer just ABS module from eBay combo onto my current ABS pump, or do I need to swap the whole combo?

Screenshot_20211118-231917.jpg
 
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Shotgunning parts at an issue isn't something I condone, This could be a bad wire (Open or Shorted Circuit), Bad Connection, Faulty Combination Meter, Faulty PCM or a Faulty ABS/Skid Control Module.

But to answer your question.....Yes, You can swap the ABS Module by itself.
 

AlphaOmega

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Shotgunning parts at an issue isn't something I condone, This could be a bad wire (Open or Shorted Circuit), Bad Connection, Faulty Combination Meter, Faulty PCM or a Faulty ABS/Skid Control Module.

But to answer your question.....Yes, You can swap the ABS Module by itself.

Thanks. I've done yet more reading after You and The Critic pointed out ABS computer is a possible issue, and there are indeed many such cases. It's a used part from eBay for $80 or so. Good to keep as a spare even if it wont turn out to be the culprit. I will also have a decent code reader/scanner next week, purchased on recommendation of a member @Trav. I need to learn how to use it

As to the wiring, everything looks good on this one owner 217k mi car. I understand that doesn't mean the wiring is not a culprit, but the overall state looks very good, including wiring and various connectors. No rust on this car (just some patina) despite it being a West Virginia car its whole life
 
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With that many miles I would be cleaning grounds and checking plugs for corrosion. I had a similar situation on my 07 Ram Laramie. I hit a big pothole on the highway and ABS and shifting and cruise became sketchy. My Zurich tester from HF led me staight to a broken wire on the left rear wheel speed sensor. I was very surprised and of couse happy to find it was that capable.
 

AlphaOmega

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My 2006 Toyota Camry v6 had a speed sensor code pop up after a heavy rain and deep puddle. Unplugged it, cleaned connections, and applied some dielectric grease before reconnecting. So far 2 years, 40k miles, and no code.
What/which speed sensor did you unplug?
 
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What/which speed sensor did you unplug?
I unplugged the one that was right under the air intake box.
My Camry has 3.0L V6 (1MZ-FE) and your 2007 Avalon has 3.5L V6 (2GR-FE), but looks like we got the same U151E transmission (which is basically a U250E, but beefed up for V6 power).


Toyota Avalon locations:

download (2).jpg
 

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AlphaOmega

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Today I've received CarScan Pro 5610 recommended by @Trav. It too, despite the box claiming otherwise, does NOT offer live data for wheel speed sensors, and ABS module.

There are plenty of ignition, intake, exhaust, emissions live data, but THE ONLY live data related to the issue that is available though the device is a singular "speed sensor", that's measured in mph only. Obviously it shows 0 mph when I'm driving. Is this a 2007 Toyota Avalon computer system limitation, or my code reader/scanner's limitation? I've now tried MSRP $120 BlueDriver and CarScan Pro 5610 with MSRP of $330... Effin annoying.

@clinebarger, perhaps you could recommend a correct code reader/scanner?

Clearing codes with either device, does not extinguish ABS light. Check engine comes back within 10 seconds of being underway
 

AlphaOmega

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I unplugged the one that was right under the air intake box.
My Camry has 3.0L V6 (1MZ-FE) and your 2007 Avalon has 3.5L V6 (2GR-FE), but looks like we got the same U151E transmission (which is basically a U250E, but beefed up for V6 power).


Toyota Avalon locations:

View attachment 78818

Which one though, NC or NT? They are both close to each other, mounted into the top side of the transmission, below the airbox
 

AlphaOmega

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Ok, I should stand a little corrected. After tinkering with the unit more, I can scan subsystems separately (A/C, TMPS, ABS/Trac/VSA, etc). Of them all, ABS/Trac/VSA produces "no connection". So ABS is offline, which, likely means it's ABS computer itself and not an individual wheel speed sensor?
I would check for ABS Module wheel speed DTC's before continuing any further.

*After looking and relooking, there is still only singular "speed sensor" live data measured in MPH (reads "0" all the time).

*** is that "speed sensor"??? "Direct clutch" sensor that's plugged into the top of transmission housing? Some other sensor?
 
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The U151E doesn't have a Output Speed Sensor, Wheel Speed is calculated off of the Wheel Speed Sensors by the ABS/Skid Control Modules & transformed into a DC-Square Wave 4 Pulse Signal that's sent to the Combination Meter then onto the ECM.

You're definitely on the right track with the ABS Module not communicating on the Can-Bus....Check Power & Ground to the ABS Module.....If good, Swap in your E-bay special!
 

AlphaOmega

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The U151E doesn't have a Output Speed Sensor

That's what I needed re-clarified. Now your below explanation makes perfect sense to me. Thanks for your guidance

Wheel Speed is calculated off of the Wheel Speed Sensors by the ABS/Skid Control Modules & transformed into a DC-Square Wave 4 Pulse Signal that's sent to the Combination Meter then onto the ECM.

Thank you very much for re-clarifying this
 
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