Brake Light AND ABS Light On


projectRanger93

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Ranger STX
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2WD / 4WD
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235/75-R15
So recently I changed the ABS hydraulic unit on my Ranger since my original one was plugged after sitting for a long time. My brakes work fine now, but my ABS light stays on as well as my Brake light. I know it's not the Rear ABS sensor because i had just fixed that harness and checked the sensor resistance, so it's still good. Before installing the new hydraulic unit i measured the pin resistances and they were not exactly the same, but similar to the original unit. My Brake light hasn't gone off either, even though the hand brake switch works (i see flickering in the indicator light) and I have enough fluid in the master cylinder.

Can one affect the other electrically? Is there a common issue that I should be aware of or is there an easy fix? How can i check if my master cylinder sensor works? Anything else I can check?

Thanks for the help.
 


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Denisefwd93

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stock, may get leveling springs in front "somday"
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The fluid level switch and or the connector on the master cylinder is a big problem for parking brake and if I remember right the ABS light also. did you do the blink code?
 

projectRanger93

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No I haven't. I'll have to dig deep under the dash for the ABS test connector. How can I verify my master cylinder sensor went bad?
 

Denisefwd93

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Total Lift
stock, may get leveling springs in front "somday"
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projectRanger93

Active member
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Location
Los Angeles, CA
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1993
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Ranger STX
Engine Type
4.0 V6
Transmission
Manual
2WD / 4WD
4WD
Tire Size
235/75-R15
sweet ill look into it, thanks for the suggestions.
 

Denisefwd93

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Ford
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4.0
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Manual
2WD / 4WD
4WD
Total Lift
stock, may get leveling springs in front "somday"
Tire Size
235
I did this exact thing couldn't believe how easy it was once I got past a mental block,
 

projectRanger93

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Ranger STX
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2WD / 4WD
4WD
Tire Size
235/75-R15
So i pulled a code 4, which relates to the abs hydraulic valve and the symptoms are also correct: brake light on and abs light on.
I recently put in a new remanufactured one from O'Reilly's but i read in the comments of the unit on their website that the wires had been switched. I measured the resistances between terminals and they weren't exactly the same as my original unit, but close. You think there's a way to reset the abs module to accept the new resistances?
 


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