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I did a search on the topic and oddly didn't get any results.
So my brake lights stay ON all the time when I drive but when I pull my E brake up they dim to normal but still are not activated by pressing in my brake pedal. I went to the mod box under the passenger side dash and checked the connection and it did not resolve the issue. besides the brake pedal position sensor is their any other thing I should check.
There is a Stop Lamp relay on the fuse panel in the passenger footwell. Lucky for you, it’s on the top of the board and not the reverse side. Try pulling the relay and see if the lights go out. Maybe the relay is stuck. You could test it with a multimeter.
I pulled those and the nudged every fuse. Which relay do I need to pull and see if it affects the light? I pulled them out, inspected and put them back in with the car off. ALSO dont know why its like this but Yestday when I started my car the Active Handling system light was on and got the service message. I went to the gym and upon starting the car the system had no message and no light. It was an exact repeat today.
EDIT: i inspected the stop lamp and it looks ok. Put it back in. no change. I need to find my multi meter, I would run a continuity test on this relay?
The relay is clearly labelled in the above diagram. If it’s a 4 pin relay, then 2 of the pins power it into the closed position. The other 2 complete the circuit. It’s the latter you want to test. When you pull the relay out, it is unpowered so there should be an ‘open’ between those 2 pins. If not, then the relay is stuck in the closed position. I’m not saying that this is the problem, but at least check it and then look elsewhere if the relay is OK. If the relay is ok, then you could probe the pin sockets that power the relay to see if there is voltage or not. There shouldn’t be unless something is commanding the relay on.
I pulled those and the nudged every fuse. Which relay do I need to pull and see if it affects the light? I pulled them out, inspected and put them back in with the car off. ALSO dont know why its like this but Yestday when I started my car the Active Handling system light was on and got the service message. I went to the gym and upon starting the car the system had no message and no light. It was an exact repeat today.
EDIT: i inspected the stop lamp and it looks ok. Put it back in. no change. I need to find my multi meter, I would run a continuity test on this relay?
This relay, did you pull it and see if the lamps went out ? I also have to ask, how old is your car battery ?
I pulled those and the nudged every fuse. Which relay do I need to pull and see if it affects the light? I pulled them out, inspected and put them back in with the car off. ALSO dont know why its like this but Yestday when I started my car the Active Handling system light was on and got the service message. I went to the gym and upon starting the car the system had no message and no light. It was an exact repeat today.
EDIT: i inspected the stop lamp and it looks ok. Put it back in. no change. I need to find my multi meter, I would run a continuity test on this relay?
Ok, so the brake pedal position sensor is a simple potentiometer…a 5 volt reference, a ground, and a signal to the BCM…when the pedal is depressed that 5 volt ref drops to maybe 4 volts or so and then the BCM see that predetermined signal voltage and applies voltage to the coil side of the STOP LAMP RELAY…so you can either have a bad BPP sensor, a bad STOP LAMP RELAY in which the “load” side of the contacts are possibly stuck closed or the BCM is always grounding the stop lamp relay control circuit…first as others have mentioned remove the relay and with the ignition in ACC or RUN see if the stop lights go out…on the stop lamp relay if you have a 12 volt test light see if you see the test light illuminated on pin 85 with the BPP sensor disconnected…you don’t want the BCM seeing the signal wire lower voltage… if you see power there the BCM’s stop lamp relay control output driver is stuck closed…that will usually be a bad BCM…if only pin 87 lit at the relay and not BOTH it’s most likely a bad BPP sensor…a new one will require a BPP sensor calibration…bidirectional scan tool will be needed for this !!…good luck !!
thanks for the info! I need to get testig voltage now. pulling the LAMP STOP relay did not turn off the brake lights
Try swapping in another relay and see if the stop lights goes out…next you can try to disconnect the BPP sensor…if stop lights go out the BPP may be bad…you can check in you have continuity between pins 87 and 30 of the relay to see if the load contacts are stuck closed…With ignition in ACC or RUN see if you have power to 2 of the 4 relay terminals on the relay if the stop lights did not go out unplugging the BPP sensor…if you lightly plug the relay in and out you will hear the relay “clicking” !!