Odd Brake Light / Turn Signal Behavior

jirwin

Goblin Guru
Took a video to try and explain the situation:

I've tried putting the wires every which way and haven't gotten what I'm looking for. My problem seems to stem from the fact that my brake/turn signal wire is normally on (hot by default). When I switch one of the blinkers on, the light blinks as it should. As soon as the blinker is off again, the turn signal/brake wire is sending power again. I don't understand why.

And top top it off, pressing the brake turns off all lights.

I'm very confused.

The tail lights did not come with the kit. They have a 3 pin system for the brakes - Ground, Running, Turn/Brake.

I have the light blue wire acting as the running light, the dark green (right) and yellow (left) acting
as turn/brake, and light green as reverse.

Does anyone have any insight/ideas?

Thanks.
 

bradr

Well-Known Member
Took a video to try and explain the situation:

I've tried putting the wires every which way and haven't gotten what I'm looking for. My problem seems to stem from the fact that my brake/turn signal wire is normally on (hot by default). When I switch one of the blinkers on, the light blinks as it should. As soon as the blinker is off again, the turn signal/brake wire is sending power again. I don't understand why.

And top top it off, pressing the brake turns off all lights.

I'm very confused.

The tail lights did not come with the kit. They have a 3 pin system for the brakes - Ground, Running, Turn/Brake.

I have the light blue wire acting as the running light, the dark green (right) and yellow (left) acting
as turn/brake, and light green as reverse.

Does anyone have any insight/ideas?

Thanks.
Unless I am mistaken, the colors should be as follows:

Brown = Parking Lights
Yellow = Left Turn/Stop
Green = Right Tune/Stop
Lt Green = Reverse
Lt Blue = 3rd Brake Light (CHMSL)

I think if you follow this wiring, it will resolve your issues.
 

jirwin

Goblin Guru
Unless I am mistaken, the colors should be as follows:

Brown = Parking Lights
Yellow = Left Turn/Stop
Green = Right Tune/Stop
Lt Green = Reverse
Lt Blue = 3rd Brake Light (CHMSL)

I think if you follow this wiring, it will resolve your issues.
If that's the case, what is my running light? Maybe I have the wrong type of lights or something. Even just keeping it simple and just plugging in turn/brake to turn/brake I still get strange behavior. The blinkers work, but the default to "on". The green and yellow wires are both "on" when nothing is happening.

Are the stock lights voltage based or something? Where it sends x volts for running and y volts for brake? That would make some sort of sense to me, because then I would have a reason for it being on by default.

The only other thing I can think of is the brake switch being messed up or something
 

Ross

Goblin Guru
clutch & brake switch issues sounds plausible to me... but it is confusing.
I agree with Brad, connect the ground & brown to both tail lights, and the green to the right side. yellow to left.
Maybe connecting both sides will help too.

Brown is your running lights. it sends 12v to the brown, and 12v to the yellow and or green. Dim is inside your LED lights.
 

jirwin

Goblin Guru
clutch & brake switch issues sounds plausible to me... but it is confusing.
I agree with Brad, connect the ground & brown to both tail lights, and the green to the right side. yellow to left.
Maybe connecting both sides will help too.

Brown is your running lights. it sends 12v to the brown, and 12v to the yellow and or green. Dim is inside your LED lights.
I'll run out there and try it again, but if I recall, the brown wire had no current at idle.
 

bradr

Well-Known Member
Check for voltage on the lt blue. If you do, the brake switch is "depressed" or the lt blue is shorted to power.
 

jirwin

Goblin Guru
Check for voltage on the lt blue. If you do, the brake switch is "depressed" or the lt blue is shorted to power.
I think I was reading something you had posted earlier stating that the brake sensor defaults to "on" if not plugged in. I'm thinking that this is my issue. Makes the most sense to me anyway. I move the pedal around now and nothing happens. I can't recreate the "everything turns off" issue from my first video now. Hopefully that doesn't mean I fried something.
 

jirwin

Goblin Guru
clutch & brake switch issues sounds plausible to me... but it is confusing.
I agree with Brad, connect the ground & brown to both tail lights, and the green to the right side. yellow to left.
Maybe connecting both sides will help too.

Brown is your running lights. it sends 12v to the brown, and 12v to the yellow and or green. Dim is inside your LED lights.
 

Rttoys

Goblin Guru
Does this thread help you at all?

 

jirwin

Goblin Guru
Does this thread help you at all?

Yeah, I've been reading that one too. See useful stuff there for sure, but I haven't been able to figure it out yet. Thanks
 

jirwin

Goblin Guru
Maybe I can take the brake sensor off and plug it in? That way I can manually actuate it by hand.
 

Desert Sasqwatch

Goblin Guru
With the lights on all the time, sounds like relay inputs are switched between the Normally Open (NO) and the Normally Closed (NC) contacts, since the blinkers/flashers seem to be working. Connecting through the NC contacts will apply power all the time and remove power when the relay is activated - making the blinkers/flashers seem to work. Stepping on the brake activates the NO contacts so the lights will go off.
 

Yustas

Active Member
jirwin, if one of brake pedal position sensor or BCM are not from the same donor - then BPP relearn requires.
If both of them are from original donor - then the issue is BPP sensor misplacement.
If you release screw - sensor has some play around anchor point, try to fix sensor in either full clockwise or counterclock position.

What happens is BPP sensor "runs" out of learned range and BCM after 5 seconds timeout just activates brake lights.
 

ctuinstra

Goblin Guru
This may sound like a stupid question, where is your ground? In all of the wire conversation, I haven't seen anything mentioned about connecting a ground to the lamp assembly? If there is a ground, did you "ohm it out" to physical ground? I know I tend to sound like a broke record always talking about grounds, but a bad ground can cause a lot of strange feedback type of issues that don't make sense. I think I know what is going on but I'm not going to jump to conclusions just yet.

Can you take voltage measurements of all of the lights from frame ground to each lamp under each condition?

1) Ignition on - No Brake
a) Marker (tail) lights left and right​
i) Left​
ii) Right​
b) Brake lights​
i) Left​
ii) Right​
c) Turn Signal (may be hard to get during flashing)​
i) Left​
ii) Right​
2) Ignition on - Brake Pedal Pressed
a) Marker (tail) lights left and right​
i) Left​
ii) Right​
b) Brake lights​
i) Left​
ii) Right​
c) Turn Signal (may be hard to get during flashing)​
i) Left​
ii) Right​
 

jirwin

Goblin Guru
This may sound like a stupid question, where is your ground? In all of the wire conversation, I haven't seen anything mentioned about connecting a ground to the lamp assembly? If there is a ground, did you "ohm it out" to physical ground? I know I tend to sound like a broke record always talking about grounds, but a bad ground can cause a lot of strange feedback type of issues that don't make sense. I think I know what is going on but I'm not going to jump to conclusions just yet.

Can you take voltage measurements of all of the lights from frame ground to each lamp under each condition?

1) Ignition on - No Brake
a) Marker (tail) lights left and right​
i) Left​
ii) Right​
b) Brake lights​
i) Left​
ii) Right​
c) Turn Signal (may be hard to get during flashing)​
i) Left​
ii) Right​
2) Ignition on - Brake Pedal Pressed
a) Marker (tail) lights left and right​
i) Left​
ii) Right​
b) Brake lights​
i) Left​
ii) Right​
c) Turn Signal (may be hard to get during flashing)​
i) Left​
ii) Right​
I'll have to wait for my friend to get here to do the brake portion as I only have 2 hands. I think I have 2 ground wires coming out of that bundle. I'm using one for all the wires. Not sure if that's ok. For the following measurements I measured to the chassis ground under the fuse box. The reverse lights work fine so I haven't included those.

For #1 I did the following.

Ignition On (no blinker)
- Yellow - Left Turn - 12V
- Green - Right Turn - 12V
- Light Blue - Running Light? - 5.5 to 6V
- Brown - Unknown - 0V

Ignition On (blinker on)
- Yellow - Left Turn - Hard to read, all over the place, started low and seemed to climb. I think the polling interval on the multimeter is too slow
- Green - Right Turn - same as left
 

ctuinstra

Goblin Guru
I'll have to wait for my friend to get here to do the brake portion as I only have 2 hands. I think I have 2 ground wires coming out of that bundle. I'm using one for all the wires. Not sure if that's ok. For the following measurements I measured to the chassis ground under the fuse box. The reverse lights work fine so I haven't included those.

For #1 I did the following.

Ignition On (no blinker)
- Yellow - Left Turn - 12V
- Green - Right Turn - 12V
- Light Blue - Running Light? - 5.5 to 6V
- Brown - Unknown - 0V

Ignition On (blinker on)
- Yellow - Left Turn - Hard to read, all over the place, started low and seemed to climb. I think the polling interval on the multimeter is too slow
- Green - Right Turn - same as left
Issues so far:
1) You shouldn't have 5.5 to 6v on the Light Blue.
2) Brown - You should have 12v if the headlights are on. This is the marker (or tail) lights.
3) You stated early on in your post "I have the light blue wire acting as the running light" - This is incorrect as Bradr stated. This is the CHMSL, or otherwise known as the third brake light. You need to disconnect this and/or put it on it's own light.
 

Karter2026

Goblin Guru
Issues so far:
1) You shouldn't have 5.5 to 6v on the Light Blue.
2) Brown - You should have 12v if the headlights are on. This is the marker (or tail) lights.
3) You stated early on in your post "I have the light blue wire acting as the running light" - This is incorrect as Bradr stated. This is the CHMSL, or otherwise known as the third brake light. You need to disconnect this and/or put it on it's own light.
I agree.

Disconnect everything. Hook up ground wire and brown wire. Get marker lights first. Then hook up the turn signal wires.
 

jirwin

Goblin Guru
Issues so far:
1) You shouldn't have 5.5 to 6v on the Light Blue.
2) Brown - You should have 12v if the headlights are on. This is the marker (or tail) lights.
3) You stated early on in your post "I have the light blue wire acting as the running light" - This is incorrect as Bradr stated. This is the CHMSL, or otherwise known as the third brake light. You need to disconnect this and/or put it on it's own light.
What voltage, if any, should I have on light blue?

I tried taking off the brake position sensor and manually actuaing it to see if it did anything and it didn't seem to change anything.

Working on finding the source of the brown wire now to re-run it.
 
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