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(SOLVED)Brake Switch issues ( no brake lights)

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Location
Orange County, NY, USA
#1
Recently was intermittently getting the P0504 (brake switch correlation) code, but brake lights still worked just fine. Figured it would be good to replace the switch just to clear the code and be set. Unfortunately this started a much more serious issue. After pulling my battery for about an hour while doing a short shifter install I also did the brake switch while battery was out. Upon reinstalling battery and starting car my brake lights no longer function at all. I have exhausted all efforts in my search for the culprit:
-Checked fuse for brake lamps
-Checked continuity of that fuse it’s good
-Fuse gets current
-Tail lights have current and still operate just no brake lights including 3rd
-pulled down wiring for brake switch connector and traced back into a bundle I know power is good in and no live wires to be found.

Only thing I’ve discovered thus far is that if I use my multimeter to probe one twilight parking light socket it will light the opposite brake light up, but will not respond to brake switch input. I’m stumped at this point and will likely have to rack up a big bill at automotive electrician because I’m sure Ford won’t figure it out. Any advice or input would be greatly appreciated. Thanks in advance


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XR650R

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#2
Bump for someone smarter than me to figger this'n out.
 


D1JL

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#3
From the Service Manuel

Brake Pedal Position (BPP) Switch Adjustment

NOTICE: Do not press the brake pedal when installing or removing the brake pedal position switch or damage to the brake pedal-mounted switches can occur.


1. Inspect all brake pedal position switches and brake pedal assembly to verify there is no brake pedal pressure unintentionally applied due to incorrect brake pedal position switch or brake pedal installation. Correct any concerns before proceeding to the next step.


2. Confirm that all brake pedal and bracket assembly fasteners are correctly tightened.


3. Using the Integrated Diagnostic System (IDS) scan tool, select DataLogger->Chassis->Braking->Brake Switch Parameters.


4. NOTE: Using the scan tool record function makes it easier to observe the brake pressure sensor readings.
Set the ignition to ON.


5. Slowly apply the brake pedal to generate the pressure graph for the BPS (brake pressure sensor) PID . The rate of brake pedal apply must not exceed 5 psi per second as indicated by the scan tool.


6. Record the initial value of the BPS PID when BRAKE_LAMP and CRUISE_CANCL change from OFF to ON.


7. If BRAKE_LAMP and CRUISE_CANCL transition to ON before the BPS PID reads 44 psi or less, the brake pedal position switch is correctly installed.


8. If BRAKE_LAMP and CRUISE_CANCL transition to ON after the BPS PID reads greater than 44 psi, replace the stoplamp switch and cruise control deactivation switch (if equipped). Clear all Diagnostic Trouble Codes (DTCs) and repeat Steps 3-6 to verify that the BRAKE_LAMP and CRUISE_CANCL transition to ON before the BPS PID reads 44 psi or less.
 


OP
radlerrrr
Messages
21
Likes
12
Location
Orange County, NY, USA
Thread Starter #4
From the Service Manuel

Brake Pedal Position (BPP) Switch Adjustment

NOTICE: Do not press the brake pedal when installing or removing the brake pedal position switch or damage to the brake pedal-mounted switches can occur.


1. Inspect all brake pedal position switches and brake pedal assembly to verify there is no brake pedal pressure unintentionally applied due to incorrect brake pedal position switch or brake pedal installation. Correct any concerns before proceeding to the next step.


2. Confirm that all brake pedal and bracket assembly fasteners are correctly tightened.


3. Using the Integrated Diagnostic System (IDS) scan tool, select DataLogger->Chassis->Braking->Brake Switch Parameters.


4. NOTE: Using the scan tool record function makes it easier to observe the brake pressure sensor readings.
Set the ignition to ON.


5. Slowly apply the brake pedal to generate the pressure graph for the BPS (brake pressure sensor) PID . The rate of brake pedal apply must not exceed 5 psi per second as indicated by the scan tool.


6. Record the initial value of the BPS PID when BRAKE_LAMP and CRUISE_CANCL change from OFF to ON.


7. If BRAKE_LAMP and CRUISE_CANCL transition to ON before the BPS PID reads 44 psi or less, the brake pedal position switch is correctly installed.


8. If BRAKE_LAMP and CRUISE_CANCL transition to ON after the BPS PID reads greater than 44 psi, replace the stoplamp switch and cruise control deactivation switch (if equipped). Clear all Diagnostic Trouble Codes (DTCs) and repeat Steps 3-6 to verify that the BRAKE_LAMP and CRUISE_CANCL transition to ON before the BPS PID reads 44 psi or less.
So does this have to be done via FORSCAN?


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OP
radlerrrr
Messages
21
Likes
12
Location
Orange County, NY, USA
Thread Starter #5
SOLVED:after a trip to the stealership it turns out my brand new Motorcraft brake switch off rockauto was defective . Installed a duralast and viola.... problem solved.[emoji28]


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