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Honda MAGNETO? or VRS.

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5 years 1 month ago - 5 years 1 month ago #27431 by Alex Ace Auto
I have an interesting case- study for you and I would appreciate your input.
I have a 2007 honda civic, NOT SI model. It has 4 wheel ABS.
It has a 2 wire type abs all around.
With the trouble codes: 12-12 Right-front Wheel Speed Sensor Short to the Other Sensor Circuit
21-11 Right-front Magnetic Encoder Malfunction (Pulse Missing)
Now I have taken thorough instruction on Pauls Chapter 21/22 Material and understand VRS vs Magneto sensors.
In this Diagram, it shows that on the Green wire +B (shown in my following attachments) should present battery voltage (Magneto).
My Snappy component tester tells me that there is ground (pink) and signal (green), NOT POWER. (VRS?)
Every sensor- the FR, FL, RR, AND RL all have a signal (Floating ground?) and a constant/hard ground. For the right front, its the green wire, with a hard ground on the pink. (unplugged)
With the sensor "loaded/connected" on a 20v scale, I am not seeing any D/C P.W waveform pass through the sensor on my Zeus scope.
With the sensor "loaded/connected" on a 1v scale I am not seeing any A/C signal.
Later switched and was able to get a 9.8v signal that was a DC pulse width, on a 20v scale at 500 ms. So this must be a Magneto P.W type..
I tried to shake my leads as instructed and see no change in voltage on the hard ground side, and the wss ground on rf side is true.
It is also important to mention THIS PROBLEM IS INTERMITTENT. No active failure- all 4 wheels respond when spun.
Checking the rf wss position I do not see a reason to think rust is lodged between the sensor and hub.
I have seen and heard of plenty of these encoders going bad and this is where I am at. Is ALL DATA'S diagram lying to me in saying that the +B should be present on the green wire as a power feed- when it's really a signal wire to the EBCM? I'm going for amplitude now and thinking to replace the wheel bearing/encoder, and clean of its WSS.


Thank you for your time hope I hear from you soon.

-Alex
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Last edit: 5 years 1 month ago by Alex Ace Auto.

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5 years 1 month ago #27439 by chief eaglebear
I foun d this cool app for Honda codes it also has ecm pinout charts on google play store

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5 years 1 month ago #27553 by CurrentDraw
Replied by CurrentDraw on topic Honda MAGNETO? or VRS.

Alex Ace Auto wrote: In this Diagram, it shows that on the Green wire +B (shown in my following attachments) should present battery voltage (Magneto).
My Snappy component tester tells me that there is ground (pink) and signal (green), NOT POWER. (VRS?)

-Alex


They are both right but a bit confusing also. Honda/Acura started using a 2 wire magnetoresistive sensors (DC signal) starting in the early 2000's which have a B+ feed and ground wires coming directly from ABS/VSA control unit. In your vehicle the "signal" is sent via the Green B+ wire to ABS/VSA unit. To scope the waveform you'll need to connect your Power side lead to B+ terminal at the battery terminal and Ground lead to the B+ Green wire.

In your wiring diagram the ABS sensor drawing looks more like a VR (AC signal) so I can see the confusion. Attached is an OE diagram which can maybe clear some things up. I would recommend selling the client dealer only parts with this type of a sensor/encoder if it does end up being your problem.
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The following user(s) said Thank You: Tyler

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