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I've mentioned this in another post. I have a P0500 code and I was curious if this code could result from a bad input/output shaft transmission sensor, also know on as a speed sensor.
 

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Speed sensor A and output speed sensor

According to the TIS, the auto trans has two speed sensors; one on the turbine/torque converter, and one on the output shaft.

Sensor A is for the turbine.

On page OBP-19, Bentley says "Input/Turbine speed sensor is "A," probably sensing the ring gear speed; thus torque converter input speed.

P0715 speed sensor A, pg OBD-19.


P0500 pg OBD-53 sensor A.

P0720 output speed sensor: ELE-626

New TIS says the sensors are inside the trans, and one must drop the pan to replace them: https://www.newtis.info/tisv2/a/en/...wiring-harness-shift-elements-sensors/DqT16b0
 

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Did you visit the link? That's the only info I have. Perhaps someone smarter than I will step up.
 

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Discussion Starter #6
I did visit it. I was just wondering if those sensors would help or be the problem. You are great help and I appreciate it
 

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Wingnut
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do you have the ABS/ASC light lit, is your speedo, cruise control working correctly? have you looked in to the ABS system for any error codes or for live WSS data? P0500 code is a DME code, road speed sensor, however, it can be triggered by a bad WSS, most likely the LF on your model if that is the problem. but it could be a trans sensor as well. as edjack stated, it manifests as a transmission error, its a cumulative error set by the DME. have you reset the code? if it returns immediately after resetting, its most likely a trans sensor, if it takes a bit of driving for it to reappear, most likely a WSS. but it is a bit ambiguous of a code.
 

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The abs, check engine, brake, and the triangle with the circle are currently lit. My cruise control does not work.
 

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I thought I was pulling the output shaft sensor and pulled off a weird, stubby, gold ended sensor on the back, top of my transmission. Near the drive shaft. What is this called?
 

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Wingnut
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I have heard before that the speed sensor a is the right front abs sensor. Is this correct?
no this isnt correct. a is a trans sensor. get the ABS codes and post them here.

edit: let me rephrase a tad....when you get the p0500 error, it could be a wheel sensor that has failed, but with the cumulative error reporting, the DME will show p0500, which is reported as speed sensor a or road speed sensor. the problem could be a WSS though.
 

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Looks like White has not read (or maybe not understood) my original post.
 

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Wingnut
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the 4 wheel sensors are lf, rf, rr, and lr. speed sensor a is what the DME defaults to when throwing an error code p0500, as defined by your scanner. BMW i believe defines it as road speed sensor. the codes for the individual wheels are not shown in the OBDII grouping of codes #s as they are not part of the OBDII protocol, they are stored in the ABS unit. as you have the ABS/DSC lites lit, the ABS is not outputting a road speed signal to the DME. DME monitors both trans output and wheel speed signal, and tosses out the P0500 with a CEL if things dont compute.
get the codes from the ABS and see what fault you have, then post them here. knowing the codes will allow us to help you. as long as you dismiss that the ABS is the problem and concentrate on the trans sensor, youre whizzing in the wind. as long as the ABS is faulted, youll always get the P0500 code, with the resulting CEL. im not discounting that the trans speed sensor could be bad, but youll never know until you find and correct the fault in the ABS system.
read posts 2 and 15 by edjack. we cant assist you if you dont help us do so.
 

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Under the lift arms
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another way of saying it..

Is a standard OBD2 reader will report it as a po500 but there are 6 other possibility that will throw that same code
Ive never had a hard time with this because ive always had access to proper scan tools

Which generally just report, which wheel sensor is bad

BUT what you might have happening is a generic report of po500 when it could be one of the other 6 codes
 
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