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Intermittent Brake Pressure warning light

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Old Sep 2, 2013 | 10:53 AM
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Default Intermittent Brake Pressure warning light

I continue to see an intermittent Brake Pressure warning light illuminate. The central warning and Brake Pressure lights illuminate when the brake is applied and then flash continually until I disconnect power at battery and reset.

Brakes work fine and fluid level is good.

Owners manual isn't much help - just says it will illuminate if one of the circuits in the brake system failed. Fluid level sensor tests correctly. The break pad wear sensors are not complete, i.e. all are missing the pad sensors. I replaced the stop light switches on the brake master cylinder two years ago. Pads and rotors are new all around last year.

I could not find this warning systems discussed in the shop manual at all.

Any suggestions on what to check?

Last edited by jwillman; Sep 2, 2013 at 01:49 PM.
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Old Sep 2, 2013 | 10:58 AM
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do you have a new brake master cylinder?
Have the pressure switches been replaced if the MC is old?
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Old Sep 2, 2013 | 11:01 AM
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Sorry Stan, Just updated the original post as you posted.

I rebuilt the master cylinder when I first got the car three years ago as it had blown the flex clutch line and all the master, slave and reservoir had been removed by the PO. New brake switches were installed then as well as a complete flush of the clutch and brake lines.
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Old Sep 2, 2013 | 11:59 AM
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it could be time for a new fresh not rebuilt brake MC to be installed,
it will come with new switches
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Old Sep 2, 2013 | 12:25 PM
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I have the same issue. New master and switches less then a year ago from Roger. Today I used the power bleeder , cleaned all grounds pressure switch wiring and tested switches, all good. Then I go around the block and breaks feel great. Pull in the driveway pull e break and warning goes off again. This happens every time I drive it what a pain in the ***. So what's the next step I want it fixed?
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Old Sep 2, 2013 | 12:35 PM
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did the warning come on before or after you pulled the E brake .
It should come on when the E brake is pulled
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Old Sep 2, 2013 | 12:39 PM
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The pressure warring light comes on after the e break is pulled
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Old Sep 2, 2013 | 01:19 PM
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you may have a wire plugged into the wrong spot on the CE panel with the early connectors its easy for the wire to get pushed out of the connector housing and then if its plugged into the wrong hole weird things will happen
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Old Sep 2, 2013 | 01:23 PM
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Thanks Stan, I'll check it out. Checking all wiring now. Just got done pulling this POS out, god I hate wire taps!!!
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Old Sep 2, 2013 | 02:44 PM
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Well removed alarm, it was only tied to a door switch, power and ground. Checked CE panel and cleaned grounds and took it for a drive. I made it 5 minutes and the pressure light came on again. Re tested break switches and tested good. What's next? Could it be the break hoses? I didn't change them yet but look to be in great condition.
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Old Sep 2, 2013 | 02:51 PM
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Look under the dead pedal,
there are 2 boxes, one with black connector and one with yellow,
check the connectors see if they are clean
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Old Sep 2, 2013 | 03:00 PM
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Thanks, ill need to check it later its just to hot now. I do have the OXS mileage counter unplugged because I can't get it to stop clicking, I guess the reset is broken. It this linked in any way?
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Old Sep 2, 2013 | 03:14 PM
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do you know how to reset the OXS sensor?
find the box and with a thin screwdriver push the black button in till it clicks this will reset the OXS sensor
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Old Sep 2, 2013 | 03:34 PM
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Yes I just pulled the cover off push in the clear button and it pops back out and will not stay down. The light goes out but still makes the clicking sound. Reset it with the OXS connector plugged in and made it 10 minutes then the brake pressure light came on again. Driving me nuts, I can't let this thing beat me....
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Old Sep 2, 2013 | 04:37 PM
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the clicking of the OXS box is normal,
the button just resets the internal counter every 30K miles,
it will set the OXS light on
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