Brake Lights
frostie
01-02-2006, 11:47 AM
Both my rear brake lights stopped working this morning at the same time. The exterior bulb malfunction icon is lit on the dash. I checked the bulbs, but both are fine.
Any ideas? Thanks.
Any ideas? Thanks.
jgattian
01-02-2006, 12:42 PM
The most common problem is the Brake Pedal Position Swith (BPP).
From the Ford manual;
"Brake lighting is controlled by the (REM) rear electronic module. The brake pedal position (BPP) switch is hardwired to the REM. When the brake pedal is pressed, the BPP switch will input information to the REM. The REM will process the information and output to the left, right, and high mounted stoplamps. Only the left and right stoplamps will provide lamp outage indication.
Disconnect the wire connector from the BPP switch (located on brake pedal arm). Measure the resistance between the BPP switch pin1 and pin 2 while applying the brake pedal.
Is the resistance greater than 10,000 ohms with the brake pedal released and less than 5 ohms with the brake pedal applied?
YES - Check REM operation
NO - Replace BPP switch."
From the Ford manual;
"Brake lighting is controlled by the (REM) rear electronic module. The brake pedal position (BPP) switch is hardwired to the REM. When the brake pedal is pressed, the BPP switch will input information to the REM. The REM will process the information and output to the left, right, and high mounted stoplamps. Only the left and right stoplamps will provide lamp outage indication.
Disconnect the wire connector from the BPP switch (located on brake pedal arm). Measure the resistance between the BPP switch pin1 and pin 2 while applying the brake pedal.
Is the resistance greater than 10,000 ohms with the brake pedal released and less than 5 ohms with the brake pedal applied?
YES - Check REM operation
NO - Replace BPP switch."
wiswind
01-02-2006, 01:37 PM
I had one of the wires to the brake pedal switch break off. I have pictures of the switch in my pictures at http://community.webshots.com/album/201931518cScpNK
This is on my '96 windstar.
On the diagrams for my '96.... It is called "Brake On Off switch (BOO).
When the wire broke off....I not only had no brake lights....
I was also unable to shift out of PARK with the engine running. I could turn OFF the engine....shift to Neutral.... Start the engine...and shift into drive or reverse. Once I would shift into PARK.... the safety once again engaged to keep it in park.
The BOO switch is also used by the safety interlock....to prevent you from shifting into gear without your foot on the brake pedal.
This switch gets its power from Fuse #7 (15A) in the I/P fuse panel.
This is the fuse block that is located just above the driver's left foot.
Check this fuse.
The power goes through the switch, to the Brake lamps (3 bulbs), Shift Interlock, Antilock Brake Control Module, and Speed Control Servo (aka Cruise control).
It is also possible that the lamps all burned out, or that there is an issue with the grounds.
This is on my '96 windstar.
On the diagrams for my '96.... It is called "Brake On Off switch (BOO).
When the wire broke off....I not only had no brake lights....
I was also unable to shift out of PARK with the engine running. I could turn OFF the engine....shift to Neutral.... Start the engine...and shift into drive or reverse. Once I would shift into PARK.... the safety once again engaged to keep it in park.
The BOO switch is also used by the safety interlock....to prevent you from shifting into gear without your foot on the brake pedal.
This switch gets its power from Fuse #7 (15A) in the I/P fuse panel.
This is the fuse block that is located just above the driver's left foot.
Check this fuse.
The power goes through the switch, to the Brake lamps (3 bulbs), Shift Interlock, Antilock Brake Control Module, and Speed Control Servo (aka Cruise control).
It is also possible that the lamps all burned out, or that there is an issue with the grounds.
frostie
01-02-2006, 02:06 PM
The high-mount light is working, so it I don't think it is the switch.
I pulled the light socket from one side. It looks burnt. Also, I can't get continuity on one of the connections. I figure the socket needs to be replaced.
What I can't figure out is why they blew at the same time.
I pulled the light socket from one side. It looks burnt. Also, I can't get continuity on one of the connections. I figure the socket needs to be replaced.
What I can't figure out is why they blew at the same time.
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