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Old 01-06-2012, 12:57 PM
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bluebee bluebee is offline
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Originally Posted by bjay27 View Post
If anyone can point me to a DIY thread for Brake Pressure sensor testing, please do so, however I coultnt find any specifics from bluebee or 540iman that specify a process.
I'm surprised since the canonical ABS BRAKE DSC trifecta thread has lots of information on testing the brake pressure sensor (but I would agree it's scattered about within the 500 posts of that thread).

The test we came up with (initially from 540iman and Max_VQ) was based, I'm sure, partly at least on this PDF:

I'll look separately for that brake pressure sensor test and include the information for you in a later post.

Originally Posted by bjay27 View Post
I have heard of erroneous diode testing even thought the wheel sensors are normal....
As I remember ... any wheel speed sensor that tested bad (when the other three were tested as good), 'was' bad (but I'd have to check the 500 posts to be doubly sure of that off-hand assumption).

Originally Posted by bjay27 View Post
I'll probably finally load up GTI and INPA for more data, as Ive been meaning to do this
Start here:
- How to diagnose the BMW amber ABS BRAKE DSC/ASC trifecta or bifecta (1) & what are all known options when your ABS control module is bad (1) & Quick99Si's explanation of why the 10-minute wheel speed sensor diode-action quick test doesn't always work, especially on brand new non-OEM wheel speed sensors (1) (2) & explanations by 540iman as to why the diagnostic tools very often (extremely often, like almost all the time) fail to properly diagnose the trifecta or bifecta (1) (2) (3) (4) (5) (6) & where to get the BMW diagnostic tools for free once you're aware of these limitations (1)

Last edited by bluebee; 01-07-2012 at 11:18 AM.
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