teeeejaay

Ok so Ive had this problem for over 5 months and its finally kicking my butt.
Ill explain a little briefly about what happened and hopefully someone out there has an idea or a fix.

The trunk light kept braking down and sagging from the roof of the trunk because my sub playing right in the trunk, my sounds guy took off the light and its housing and installed a LED strip instead. He connected the positive and negative and hooked up the lights. Worked fine.

Then about 5 months ago the light was disconnecting from the wires. I said ahh, lets take it off till I get a new LED strip to hook up. During the time that it was disconnected it might have touched each other positive and negative. So I then put electrical tape over it to prevent that.

What im not sure is that if the wires touched each other and shorted something? Cause my dash shows that the trunk is open, but it really isn't. I slam it down and still nothing...

So for the past 5 months I have been getting dead batteries, broken alternator, starter broke, the trunk light is on and irritates me so much it makes the noise like im not wearing my seatbelt.

The alternator was probably because it had oil all in it from my valve cover that was leaking, fixed the leaking problem by changing the valve cover gaskets. And then bought a new alternator.

I replaced my starter, not sure what caused it but it was the original one. I have a 04' with 140xxx miles so maybe just old.

The dead batteries, I went through 2 new batteries already and Im guessing it was because my alternator was messing it up and not charging it properly, plus what ever is drawing power from the battery is killing it as well.

What im thinking to myself is that maybe the sensor isnt reading that the trunk is closed? So one of my mechanic friends said to take the sensor, cut the wires to disconnect it from the light and close it out by connecting it together. He said that should take away the light on my dash. NOPE still on. so idk what the heck is going on... What I was thinking is that the car thinks my trunk is open so its trying to "POWER" the light thats supposed to be connected in my trunk, but I took out the light so its not powering the light. Im guessing that the car is just always pushing power to my trunk even when Im not even by the car? It might be thinking that its open so its always draining the battery. Does that make sense? Someone can correct me if im wrong, but I cant seem to correct this issue of dying batteries and the trunk open light stays on.

If someone would be able to help me out that would be so awesome, Ive been meaning to get a voltage tester and try to check to see which area is drawing the power, so I see this video from youtube. and am heading to radio shack now to get the things for this tester.

Another dumb question, since my battery currently died 2 times and got recharged at orileys once, is it still okay? I heard its not always good to keep charging up the battery. Any input on keeping battery or getting new one would be appreciated.

Does anyone know if there is any more sensors for the trunk besides on the latch area it connects to when it closes?

Im on the verge of taking my car to the STEALERship and I wouldn't want to if I could fix this myself. I almost give up on the issue, its been for ever since I could see my actual milage on my car, I cant even reset the oil change warning lol. I would hate to take it to the stealership and its something really simple and I end up paying $500 LOL

Please helpppp! Ill be heading to radio shack in about 30 min and then to checkers to get the voltage tester and to charge my battery.

mzilvar

iTrader: (3)

The trunk lid sensor is controlled by the MICU and it communicates to the cluster over the B-CAN network on the car.

There actually isn't a sensor on the wires anywhere, I'm still trying to find some more schematics on it in the FSM, but it's around pg 22-300, to see where it comes into the MICU at.

I'll see if I can figure out just how the sense works, but I don't see a sensor anywhere in the circuit like the doors have on them for when they're open or closed.

There are two switches in the circuit, the trunk lid opener main switch which is the one in the glove box that you would flip if you were giving someone a valet key and didn't want them in the trunk and the trunk lid opener switch that you hit to open it on the lower part of the driver's dash.

Try disconnecting the one on the dash panel, does that make the trunk open indicator go out?

mzilvar

iTrader: (3)

So the sensor you're looking for is actually right on the trunk latch, when you open the trunk if you remove the trunk liner on the trunk lid you'll see a connector with 3 wires on it going into the latch.

Pg 22-211 of the FSM has the info you're looking for, check continuity (resistance with an ohmmeter) between terminals 2 and 3 (as you're looking at it with the clip on the connector on top terminal 3 is on the right, 2 in the middle) and there should be continuity that way with it open.

That's testing it on the switch itself, not the wires that were disconnected.

When it's closed you should not have continuity between the same two pins, not sure how you're going to test it with the trunk lid closed.

I'm pretty sure the trunk light is on the interior light switch with the other interior lights (glove box, rear console), so it shouldn't always be on when you open the trunk only if you have the headlights on.

...

So the trunk lid light is only on if the trunk is open AND the interior lights are on (glove box, rear console) e.g. headlights on. The switch inside the trunk lid latch is what controls that and the indicator on the MID comes on as a result of an input to a MICU.

If you connect the wires like your mechanic friend said the latch will always appear that the trunk is OPEN to the MICU so your indicator will never shut off.

If you just disconnect the connector on the latch your indicator should shut off.

mzilvar

iTrader: (3)

Don't lock yourself out of the trunk the motor to open it is on the 3 prong connector you need to disconnect to test it I don't know if it will latch with that connector off but if it does only way to open it is from in the trunk

Haha just stuff a buddy in there while you test

Don't actually stuff someone in there though haha

nfnsquared

Crawl inside the trunk and have someone close the trunk lid. Does the trunk light go out? If it does, it's not the switch. (Or you could open the pass through and look to see if the light goes out.) My guess is that the wires shorted and screwed up the MICU...

The dead batteries could be a faulty HFL. Search the forums for that issue, tons of info on that.

teeeejaay

Ya i seen the sensor on the trunk latch area, I disconnected that a couple months back, might need to buy a new one?


UPATE: I tested the car to see which was the ones drawing power from my battery (Using a Digital Multi-Tester), so I connected disconnected the negative terminal of the battery, clipped the black side of the tester to the negative terminal on the battery and connected the red part of the tester to the negative ground wire. My settings was on DCA 200M, the meter read 7.0-7.1. I started taking out each fuse one by one starting with the engine fuse box. No luck there with the power decreasing. Went into the driver side fuse box. Went through every fuse again. There we go, I got a decrease. What was drawing the energy was the fuse 7.5A for the interior lights. I pulled that one out and it went down from 7.1 to 3 then I took out the one next to it (7.5A spare) and it went down to 2.

Now Im stuck with no power locks, no A/C, no clock on my dash, no power seats Horrible lol!!! Im going to look into this HFL issue. Hopefully I can figure out which is drawing the power.

teeeejaay

Only thing is I cant check the light if its on when the trunk is closed because I removed the whole housing for the light and removed the LED strip I had there. So theres just wires now. Any way to test that? Also have a huge sub box and a 13.5" JL W6 in there lol. I could only fit a small dog in my trunk, maybe a little kid. No adult can fit in there to check it.

nfnsquared

Ahhh, if you have the light disconnected and it's two wires isolated, then that circuit is dead. Even if the switch was bad and stuck in the closed position (trunk open/light on), there is no power coming from the fuse box to complete the circuit.

But that same fuse (#6) also controls the HFL, so I believe you may have discovered the issue behind the battery drain. Read the HFL thread for more info.

But none of this explains why the MICU is showing "Trunk Open"... unless it got shorted out during the previously mentioned installation mistakes...

And I highly recommend purchasing the Electrical Troubleshooting manual. Easily worth the $50 IMO.

And lastly, don't forget about the emergency trunk release handle...

teeeejaay

Oh wow, I hope that fixes that issue when I go and disconnect my HFL. Im working on my car right now. So ill be doing more test to see if disconnecting the HFL helps the drain..

How do I fix it if it got shorted? Do I need to purchase something? have anything reset? Fk'ed for life? LMAO hope not. thanks for the replies

nfnsquared

Sorry, no clue on the possible MICU issue. Could be expensive...

Keep us updated on the HFL situation. Hope that resolves the battery drain issue.

mzilvar

iTrader: (3)

I've had my HFL out of my car for over a year now. My first one lasted a very long time, I replaced it and less than 6 months later it was dead again. I just removed it and left the connector hanging off in the roof, no harm there and everything else works fine.

With regard to the sensor for the trunk lid, it's in the latch mechanism, so if that's the problem then it'd need to be replaced.

Only thing is if you leave it disconnected you won't be able to open the trunk as the motor in the latch mechanism will never work, it functions off of pins 1-2 on the same connector. Basically pin 1 is for the motor, 2 is a ground that is shared and pin 3 is for the light and also goes to your MICU.

But you can test it that way, as long as the wires aren't soldered together on the wiring harness like that mechanic said to do simply disconnecting the connector should make your trunk open indication on the MID go away while the trunk is actually open.

If that's the case, where it goes away with the connector disconnected then your MICU should be perfectly fine and then it's probably your latch that's somehow internally shorted pins 2-3 together causing it to always appear that the trunk is open to the MICU.

I would revert those wires on the latch to the way they were stock, and disconnect the connector from the trunk latch mechanism and see if the indicator on the MID goes out. If it does you know exactly where the problem is with that and it would prove the MICU to be good.

With regard to your trunk light NFN is right, with those wires disconnected it'll never draw any current and cause any drain on your battery. However, with pins 2-3 soldered together like the mechanic said to do it applies a ground to your MICU on one of it's pins, so it may draw a little more current since it thinks the trunk is open as a result and it completes another circuit in the MICU.

The MICUs are always on though, even when the car is off they have some parasitic draw.

Look at the latch first, the MICU is probably expensive. The only way to really isolate if it is the MICU or the latch is by testing the latch switch anyhow. I'd think a latch with a motor in it is probably going to be fairly expensive as well though.

nfnsquared

I totally missed that paragraph in the OPs first post. Yep, if the dude shorted those two together, then that would explain the "Trunk open" light on the dash. He must have assumed that a closed circuit would mean "trunk closed". Oopsy

That would be the blue/yellow wire shorted to the black wire. (for 04-05 TLs).

teeeejaay

When I opened mine up to see if the HFL is the situation, I have the homelink there? Idk if its the same but it seems like that runs the light controls since its all connected by a mother board. I kept it plugged in.

teeeejaay

So i tried to unplug the trunk connector the one with three wires and plastic connector. Trunk light still on. Then tried to close the trunk and check if the trunk open is still blinking on the dash. Its still blinking that the trunk is open even after I unplugged the wires in the trunk. Would this mean my MICU is fried? I would buy another one if I can figure out if thats the main problem. Would buying a new sensor thing fix the problem? Thats like $50 instead of the $300 for the MICU.

mzilvar

iTrader: (3)

I wouldn't buy a MICU just yet.

Are the wires on your trunk latch wired they would be stock? There are no splices by the latch correct?

The wires where your trunk light was are disconnected correct?

Another possible culprit is the wire from your trunk light that goes to the connector with 3 pins in it on the trunk latch. If that wire (the BLU/YEL) wire has shorted to ground somehow then that'll create your problem.

If your trunk light wires are out and the BLU/YEL wire that is disconnected from the light is somehow stuck to ground then that'll do the same thing.

What I'd do next is with the trunk latch connector disconnected measure continuity (resistance) with a DMM from pin 3 of the wiring harness side of that connector (the BLU/YEL) wire to ground (any point of metal in the trunk).

Is there continuity? If so that's the problem, figure out where the wire is shorted to ground.

Maybe the tape came off and the wire is shorted to ground or the wire has rubbed through somewhere and is shorting to ground.

Is your trunk open indicator intermittent at all? Does it flicker sometimes or is it just solid as being on all the time?

If it's intermittent where it comes on and off that would make it appear like a wire is being grounded and vibrations are making it disconnect from the ground at times.

Do the front and rear map lights, the lights in the window visors and the door courtesy lights still work?

If so that would prove the ground hasn't made it over to the GRY/BLU wire where your trunk light was, that is the positive wire. If that one gets grounded a fuse should blow and your other interior lights wouldn't work. It would also cause the fuse to either continually blow or it would leave a large drain on the battery since it goes directly to the battery.

That also happens to be on fuse #6 where you had your large drain at.

You could pull fuse #6 in the under dash fuse panel and then check continuity from the GRY/BLU wire to ground as well, that side of it might have a ground on it as well. Make sure to pull the fuse before checking it for continuity to ground, that wire has power on it all of the time.

It could be grounded in a lot of different places, but more than likely is where you were messing with the trunk light at, in your trunk.

teeeejaay

Thanks for taking the time to help out.

mzilvar

iTrader: (3)

I think maybe if you drive with the trunk open it beeps at you, never tried it lol .. but that may explain the beeping.

teeeejaay

I know it beeps and shows that I need to do maintenance but i believe thats just cause I didn't get to reset my oil change thing. I did the oil change but couldn't see the dash because it still has the Open trunk thing going on lol.

Im going to check the things you brought up and I will get back to you. Doing it in a couple of hours.

"If your trunk light wires are out and the BLU/YEL wire that is disconnected from the light is somehow stuck to ground then that'll do the same thing."
I think that might have happened how do I check that?

teeeejaay

What I'd do next is with the trunk latch connector disconnected measure continuity (resistance) with a DMM from pin 3 of the wiring harness side of that connector (the BLU/YEL) wire to ground (any point of metal in the trunk).
Ill try and check this as soon as i get home.

Is there continuity? If so that's the problem, figure out where the wire is shorted to ground.

so I took out fuse #6 and checked the blue/yellow and it had high numbers. I also checked the blue yellow by the trunk latch and its u plugged and still ran .41 so it had power to that also?

Does this mean I don't need to replace the MICU just need to find where it's grounding out?

mzilvar

iTrader: (3)

It had .41 ohms of resistance?

If that's the case, then that wire has a ground on it somewhere. If you measured resistance from the BLU/YEL wire to the chassis and got 0.41 ohms that's effectively a short and is causing your problem.

Make sure to measure ohms, the omega symbol on your DMM.

Not looking for DC Voltage here right now.

That wire looks like it's only in the trunk, can you access where your old trunk light was and the light side of that wire or are you not able to get to it?

Only checking it on the wire in the trunk right? Not directly at the fuse.

If that's the case then I'd say yah, that's your problem.

There's another step to isolate the MICU since it has a pin on that wire as well, but I'd check the light first and see if the wire abraded through somewhere.

I think the last step to make sure the MICU itself isn't grounded would be to pull the battery cable off and disconnect the MICU (passenger fuse box) and then check that BLU/YEL wire for continuity to ground again. If the continuity is gone then the MICU somehow shorted that pin to ground, if not then it's on the wire.

I've never removed the MICU before though, so I'd check the FSM to make sure it's done right first.

Pulling the MICU is probably a PITA though, I'd check the ends of the wire that are disconnected first and see if it abraded on metal somewhere in the trunk, maybe a sharp spot near where the light mounts.

teeeejaay

It had .41 ohms of resistance?

If that's the case, then that wire has a ground on it somewhere. If you measured resistance from the BLU/YEL wire to the chassis and got 0.41 ohms that's effectively a short and is causing your problem.

Make sure to measure ohms, the omega symbol on your DMM.

Not looking for DC Voltage here right now.
ill double check this

That wire looks like it's only in the trunk, can you access where your old trunk light was and the light side of that wire or are you not able to get to it?
i can access that area. What it was two wires plugging into the back of the plastic connector then that was connected to a led strip.

Only checking it on the wire in the trunk right? Not directly at the fuse.
yeah it's only at the trunk wires, not the fuse area.
If that's the case then I'd say yah, that's your problem.

There's another step to isolate the MICU since it has a pin on that wire as well, but I'd check the light first and see if the wire abraded through somewhere.
would I need to check the wire from the plastic connector to the fuse box? So pretty much strip the interior on the side the wire is running?

I think the last step to make sure the MICU itself isn't grounded would be to pull the battery cable off and disconnect the MICU (passenger fuse box) and then check that BLU/YEL wire for continuity to ground again. If the continuity is gone then the MICU somehow shorted that pin to ground, if not then it's on the wire.

I've never removed the MICU before though, so I'd check the FSM to make sure it's done right first.

Pulling the MICU is probably a PITA though, I'd check the ends of the wire that are disconnected first and see if it abraded on metal somewhere in the trunk, maybe a sharp spot near where the light mounts
should I try wrapping anything with electrical tape? Like the plastic connectors?

mzilvar

iTrader: (3)

Wire to the MICU could be a problem too, but I don't know where the car makes that junction at. The OEM isn't going to tap a wire the way people normally do with vampire taps and stuff like that, they'll do it at a terminal block or something like that.

So that could be a problem, whereever the junction is from that BLU/YEL wire to the MICU, but I have no clue where that junction is made at.

Seems more likely that the problem is somewhere around where it was messed with when the LED was put in.

The plastic connector shouldn't really be a problem, but I'd be certain the ends of those wires that are cut and the pins that are exposed right now have electrical tape on them to prevent them from shorting to anything.

Could just put some heat shrink on the wire so it extends past the end and shrink it over it, so you don't have the adhesive all over the wire or connector if you find it and return the wires by the latch back to the way they were stock or re-use the light later.

So the wires on the connector for the light were never cut? I thought maybe it had been cut and soldered to an LED lol .. I'd check out the wires though. If its registering that resistance to ground of around 0 ohms thats a short somewhere.

teeeejaay

So by me taking out the #6 fuse it should not have any power in the blu/yel or gry/blu

Sorry I keep asking questions, what should I do with the trunk latch/sensor part? Should I buy a new one of those? Right now the wires that go to the trunk latch is open. I cut them from the sensor.

teeeejaay

I have quite a few pages my friend printed for me of the electrical.

Heres one might help? I stripped the back seat, the c pillars, the cover that goes over the rear speakers, the trunk linking for the trunk door. I see that the wire from the light goes into the car through the middle of the rear speakers, then splits into another set of wires that leads to the stock sub area. I disconnected and removed the sub a long time ago the wire with the connector is just dangling there. Then the wires from the trunk leads to the side of the rear driver side next to the seat then down into the floor area. Im gonna keep checking the area and hope I find something obvious. As of right now I cant find anything open. But ill check more.

teeeejaay

teeeejaay

Also wanna mention that the fuse #6 isnt popping anymore. Does this still lead me to believe its a grounding issue with the trunk wires?

Or did i fry something?

mzilvar

iTrader: (3)

Can't see the image.

Was fuse #6 blowing all of the time?

With it out the GRY/BLU wire would be flat, that is correct there shouldn't be any voltage on it.

Interior lights also wouldn't work. All of them would be out with fuse 6 pulled.

If it's an area you hadn't done much, I wouldn't think the wire got damaged there. Those bottom trim pieces come out too, I've run wires through that tray all of the way to the interior fuse panel before. I wouldn't think anything would've gotten damaged in there, but I'd imagine the wires probably run that way to the interior fuse box.

Don't check continuity from ground to a wire with voltage on it. If you're checking resistance the wires shouldn't have any power on them.

Edit: Thats the same schematic I've been looking at lol, just it shows it arranged a little different and some of the junctions.

teeeejaay

I believe I blew a 7.5A fuse before, but don't remember which one I changed. I wouldn't doubt it if it was #6

The interior lights don't work when fuse #6 is out. Only the trunk wires have power through them.

mzilvar

iTrader: (3)

Yah fuse 6 is for all the interior lights and is 7.5A.

What do you mean only the trunk wires have power through them?

teeeejaay

I tested the wires in the trunk to see if it had power trough them after I took out #6 and they did. But the interior lights in the car went out after taking the fuse out.

Do you recommend closing the wires or just replacing the thing I cut off. The sensor on the trunk latch. Idk if that will affect anything ?

mzilvar

iTrader: (3)

Oh, so there's voltage on the BLU/YEL wire with fuse 6 pulled? That would be odd, because that wire shouldn't have a voltage on it, especially with fuse 6 pulled.

mzilvar

iTrader: (3)

Is the connector on the trunk light disconnected from the trunk light lens? Do you have that anymore? Just curious if its there or not.

Can you take a photo of your trunk lid latch switch with the way you have it wired and of the trunk light connector so I can see whats going on with what wires were cut and how things are at on those two connections?