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Old 12th August 2016, 05:27   #9
Mike Noc
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Rover 75 CDT Manual Connoisseur SE, Rover 75 CDT Automatic Connoisseur SE & a Freelander Td4.

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Quote:
Originally Posted by larryr123 View Post
Thanks Chris, that's one off the list -- any idea what could still be causing the ABS to kick in at low speed?
Follow Harry's advice below and make sure you rotate the wheel slowly to check each magnetic reluctor segment.

Quote:
Originally Posted by HarryM1BYT View Post
Reading that, suggests you are misunderstanding how to carry out the test...

It is NOT just a matter of checking the voltages, but of marking the tyre where the voltage changes. A light coloured crayon, with a brick or similar as a fixed marker works well. That ensures that a full continuous set of changes of voltages/ pulses appear around the circumference of the wheel/tyre. You may need to repeat it several times to be sure the pulses appear without fail.

The judder happens when pulses signals fail to appear, when they are expected. Most likely they will be missed at lower speeds, hence the low speed judder you are experiencing.

T4 and other diagnostics will not see it as a fault, because it is doing more or less what it is supposed to be doing - generating mostly regular pulses.
Have done this a few times now and it is a very good way to test all the ABS sensors and magnetic reluctor rings.

Last edited by Mike Noc; 12th August 2016 at 06:16..
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