View Single Post
  #21  
Old 01-22-2013, 04:11 AM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,315
Mein Auto: 02 BMW 525i M54 auto 130K
Quote:
Originally Posted by Microflight View Post
I back probed the three wires going to the sensor. Violet/black measures 4.36 against Blue/Black and 5 volts against the strut tower nut. The Violet/Black measures 0.64 volts against the strut tower nut. (Interestingly the net voltage of the two wire is 5 volts.)

I measure the White/blue with no brake pressure and the reading was .64 volts. With some brake pressure the reading was 1.25 volts. And with a lot of pressure the reading was 2.5 volts.
This is great information!

To my knowledge, unfortunately NOBODY yet has posted a PICTURE of the actual testing procedure.

Nor, to my knowledge, has anyone actually 'needed' to replace the brake pressure sensor when they had the trifecta.

So, whatever YOU learn, please let US know as you're on ground rarely traveled!

Quote:
Originally Posted by Microflight View Post
is there a furred trouble shoot on the control module
The only test of the control module that I know of that is even close to reliable requires you to Exacto knife open the control unit to lift off the cover.

Once the cover is off, then toothpick the 7th aluminum wire to see if it has lifted off its gold bondpad. If it lifts up, then you KNOW it's the control module.

Gory details with dozens of pictures are found by typing /abs F3 in the bestlinks:
- How to test and repair an E39 Bosch 5.7 ABS control module (1)


Note: if you decide to send out the ABS control module to the rebuilders, this will help:
- What are all known options when your ABS control module is bad (1)
__________________
Each repair should invariably add to our knowledge base by the process of inexorable incrementalism.
Your job, in return, is to read the suggested threads, where the best people will always add value to those threads, either by pictures or by descriptions, so the next person with the same problem stands on your shoulders.
See also: E39 Bestlinks & How to easily find what you need
Reply With Quote