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PSD v ABS

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Old Feb 2, 2014 | 01:45 PM
  #1  
fonetico's Avatar
fonetico
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Default PSD v ABS

I suspect I need some expert opinions on the erratic behaviour of my braking system and the bizarre noises emanating from the PSD.

Some months ago I was experimenting with various solutions to improve the pathetic performance of the emergency brake. At a certain point during my trial and error methods the PSD woke from the dead and would go into spasms of constant fervid activity, suddenly activating at inappropriate moments. Part of my programme to fix the emergency brake was to change the rear rotors and this seemed to also resolve the PSD issue. At the time, I wondered whether the ABS sensors were somehow responsible and changing the rotors gave them a new lease of life.

Last week the PSD once again woke from hibernation and the dash light began flashing and the PSD pump started whenever the car was stationary. At the same time, the ABS would activate. It's a disconcerting feeling to be sitting at traffic lights with both the PSD and ABS vigorously shaking the car and the brake pedal shaking the fillings in my teeth.

So, is it a reasonable assumption that the ABS sensor is toast? Is there a relationship between the electronics that control a spinning wheel and a locked wheel?

The mind boggles!

Please help.
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Old Feb 2, 2014 | 01:59 PM
  #2  
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ABS and PSD functions are integrated in the same control unit as the PSD system relies on the ABS wheel sensors to know when to engage to control rear wheel spin. I'd start with a thorough cleaning of the ABS wheel sensors, all the grounds for the wiring harnesses at the wheels (these shield the ABS signals) as well as all the main grounds in the electrical system, and clean the lateral accelerometer under the left seat. Then disconnect the battery and remove the harness plug from the ABS/PSD controller and ensure the connections are sound. Also inspect and clean the power connections at the PSD pump unit aft of the left rear wheel.

Mike
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Old Feb 2, 2014 | 02:40 PM
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fonetico
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Thanks Mike.

I had hoped there'd be a simple fix but I sort of suspected something like this.

Glyn
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