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I did check the pad. And to make sure it wasn’t the pad/switch I replaced the switch and then pushed it in all the way with a pen and the lights were still on.
Then you should see a constant 12v at both or all three brake light may be the pnk/blu wires.
Either at the brake switch or at the lights..a 12v that will not go away with the brake switch position.
If the signal is constant despite the brake switch setting, I would disconnect (cut) the output pink/blu from the brake switch to see whether the lights stay on.
If the brake lights stay on, there is a short on the pnk/blu brake light power and you continue from there.
I don't see the BCM being involved with the brake lights...only the turn signals and hazards.
The BCM tells the IPDM to close the tail light relay which controls all the parking lights.
Brake lights aren't an issue as far as I can tell because that circuit is functioning properly according to what the OP has said, they turn on when you press the brake pedal, they turn off when the brake pedal is released.
The issue appears to be only the rear parking lights, and with part of that circuit potentially just hanging out in the open (license place light wire is broken and not attached) then you can have all sorts of issues. Look up section LT - Lighting in the FSM for the diagrams, you'll see what I'm talking about.
Just to verify OP the FRONT parking lamps turn on when you manually use the light switch to turn on parking lights correct?
Just read that the spoiler light is also turned on, looks like it IS possibly a brake light issue. That circuit is not controlled by the IPDM or the BCM, it's a 12v switch that goes directly to the tail lights and CHMSL. Remove the switch and use a digital multimeter to verify that pins 4 and 3 open and close as the switch is actuated. Just because it looks good on the outside doesn't mean it's actually working, might be broken inside the switch.
The BCM tells the IPDM to close the tail light relay which controls all the parking lights.
Brake lights aren't an issue as far as I can tell because that circuit is functioning properly according to what the OP has said, they turn on when you press the brake pedal, they turn off when the brake pedal is released.
The issue appears to be only the rear parking lights, and with part of that circuit potentially just hanging out in the open (license place light wire is broken and not attached) then you can have all sorts of issues. Look up section LT - Lighting in the FSM for the diagrams, you'll see what I'm talking about.
Just to verify OP the FRONT parking lamps turn on when you manually use the light switch to turn on parking lights correct?
Just read that the spoiler light is also turned on, looks like it IS possibly a brake light issue. That circuit is not controlled by the IPDM or the BCM, it's a 12v switch that goes directly to the tail lights and CHMSL. Remove the switch and use a digital multimeter to verify that pins 4 and 3 open and close as the switch is actuated. Just because it looks good on the outside doesn't mean it's actually working, might be broken inside the switch.
I thought he said his problem actually was the brake lights...not the parking lights as he originally thought.
I'll defer to you as you know the G35 better than I do..
The BCM tells the IPDM to close the tail light relay which controls all the parking lights.
Brake lights aren't an issue as far as I can tell because that circuit is functioning properly according to what the OP has said, they turn on when you press the brake pedal, they turn off when the brake pedal is released.
The issue appears to be only the rear parking lights, and with part of that circuit potentially just hanging out in the open (license place light wire is broken and not attached) then you can have all sorts of issues. Look up section LT - Lighting in the FSM for the diagrams, you'll see what I'm talking about.
Just to verify OP the FRONT parking lamps turn on when you manually use the light switch to turn on parking lights correct?
Just read that the spoiler light is also turned on, looks like it IS possibly a brake light issue. That circuit is not controlled by the IPDM or the BCM, it's a 12v switch that goes directly to the tail lights and CHMSL. Remove the switch and use a digital multimeter to verify that pins 4 and 3 open and close as the switch is actuated. Just because it looks good on the outside doesn't mean it's actually working, might be broken inside the switch.
are you talking about the brake switch. If you mean that I already bought a new one and replaced it so I don’t see the new brake switch not opening and closing properly but if you still think it’s that I will deff test it
After seeing that video I'm almost certain you have broken wires in the trunk. The flicker is a dead giveaway.
What happens if you open the trunk while someone is repeatedly pressing the brakes? It would almost be GOOD if it would just short out and blow a fuse so you know exactly which circuit is the problem.
Have you checked for the license plate wiring to make sure it's not grounded out, intermittent grounding with a lot of resistance (corroded wire barely touching the other conductor or exposed corroded metal) will cause issues that look like that flicker as well, since you already know there's a damaged part of the circuit I would start there to make sure it's not the culprit.
The brake lights get their power directly from the brake switch, ring out those wires back to the switch and see what the digital multimeter says.
Also, there are TWO switches on the brake pedal, when you unplug the switch you replaced you should not have any brake lights, correct?
Just want to verify you are working on the correct switch.
I tested both switches. The bottom one I believe is cruise control and the top one is the brake. That flicker only happened that one time and I could not get it to happen again. As far as opening the trunk of you mean pressing the brake while the trunk is open I did try that and the same thing happened. But if you mean repeatedly pressing the brake while opening the trunk I have not tried that.
you mention the license plate wire and that sounds like it could be that. When I noticed my license plate wire was snapped I just kind of shoved the wire back up where it came from so it wouldn’t dangle. That’ll be the next thing I check for sure.
Unplug the other switch too, the brake lights will NOT turn on with the actual brake switch disconnected. It's possible you've been working on the wrong switch.
Unplug the other switch too, the brake lights will NOT turn on with the actual brake switch disconnected. It's possible you've been working on the wrong switch.
from my research it looks like the top one is the break switch, the new brake switch I bought had a white tip that autozone looked up the switch for me and it has the same white tip where as the bottom one has a brown tip. I’m for sure going to try it tomorrow because I’m just lost at this point and I feel it can be anything at this point. Will keep you updated. Thank you for all your help!
So I unplugged both switches the brake and cruise control switch and the lights were still on and yes physically unplugged them not just took them out of the holders. I took the license plate light out and disconnected it so there’s no way that could be improperly grounded I’m completely stuck
