# Posted before with no replies.... Please help if you might know issue Thanks!



## Snipesy (Dec 7, 2015)

Does the radio turn off when you open the door?

If not. Door switch. Eh just leave it.

If it does. Wiring harness or internal BCM failure.


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## 16.399981 (May 4, 2020)

Snipesy said:


> Does the radio turn off when you open the door?
> 
> If not. Door switch. Eh just leave it.
> 
> If it does. Wiring harness or internal BCM failure.


Thanks so much Snipsey.....Radio does NOT turn off when I open door. "EH just leave it" I am considering selling the car and don't feel comfortable selling it with this problem as if the cars sits for more than 3 days battery will drain. I am going to youtube how to remove door panel to remove and replace door switch. Thanks again for you input as you were the first person and only person in 28 days since first post to reply and help which is greatly appreciated. Stay well.


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## Snipesy (Dec 7, 2015)

LTZ RS 16 said:


> Thanks so much Snipsey.....Radio does NOT turn off when I open door. "EH just leave it" I am considering selling the car and don't feel comfortable selling it with this problem as if the cars sits for more than 3 days battery will drain. I am going to youtube how to remove door panel to remove and replace door switch. Thanks again for you input as you were the first person and only person in 28 days since first post to reply and help which is greatly appreciated. Stay well.


It will just naturally turn off after about 30 minutes. Or when battery reaches a certain point. It’s not the _biggest _deal in the world.

Unfortunatey I dont know how to replace the switch. I don’t think it’s difficult though.


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## 16.399981 (May 4, 2020)

Snipesy said:


> It will just naturally turn off after about 30 minutes. Or when battery reaches a certain point. It’s not the _biggest _deal in the world.
> 
> Unfortunatey I dont know how to replace the switch. I don’t think it’s difficult though.


Unfortunately the lights mentioned do not shut off. They stay on all the time. Not even after 30 minutes. Fully charged battery or time does not matter. Thanks again for your input!


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## Snipesy (Dec 7, 2015)

LTZ RS 16 said:


> Unfortunately the lights mentioned do not shut off. They stay on all the time. Not even after 30 minutes. Fully charged battery or time does not matter. Thanks again for your input!


Interesting. Well it’s suppose to.... Although that could easily of been an oversight by GM.

Does the radio at least eventually naturally shut off? The radio controls it’s own power through the CAN BUS.


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## 16.399981 (May 4, 2020)

Snipesy said:


> Interesting. Well it’s suppose to.... Although that could easily of been an oversight by GM.
> 
> Does the radio at least eventually naturally shut off? The radio controls it’s own power through the CAN BUS.


Yes....everything else shuts off as normal. thanks


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## plano-doug (Jul 1, 2015)

LTZ RS 16 said:


> ...Radio does NOT turn off when I open door.


Let's start there. It could be the switch (in the latch), or it could be in the wiring to/from the switch. The wiring harness in the driver's door jamb gets lots of use, so it's a common place for a wire to get damaged due to all the flexing.

But before chasing that, try shooting some WD-40 in the latch. Using the plastic tube, shoot a little, close and open the door, and repeat. I've repaired at least one car - 2002 Impala, I think - using that technique (garnered from the Impala forum, as I recall).

The idea is to get the car to recognize the door is open, then see what symptoms remain, if any.

HTH.

Doug

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## 16.399981 (May 4, 2020)

plano-doug said:


> Let's start there. It could be the switch (in the latch), or it could be in the wiring to/from the switch. The wiring harness in the driver's door jamb gets lots of use, so it's a common place for a wire to get damaged due to all the flexing.
> 
> But before chasing that, try shooting some WD-40 in the latch. Using the plastic tube, shoot a little, close and open the door, and repeat. I've repaired at least one car - 2002 Impala, I think - using that technique (garnered from the Impala forum, as I recall).
> 
> ...


Hi Doug...thanks so much for reply. As soon as I received your message I went to the garage and lubricated latches and hinges on all four doors. Opened and closed each many times and then repeated it twice for each door. Left the doors open for 15 minutes and then closed all doors. Lights stayed on while doors were open..... not the dome lights and other dash lights as they shut off as normal. Unfortunately the lights are still on. As reminder, they are only the ones on the steering wheel, all four door switches for the windows and locks, truck release and drive selector. I really appreciate you replying and trying to help.


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## plano-doug (Jul 1, 2015)

LTZ RS 16 said:


> Hi Doug...thanks so much for reply. As soon as I received your message I went to the garage and lubricated latches and hinges on all four doors. Opened and closed each many times and then repeated it twice for each door. Left the doors open for 15 minutes and then closed all doors. Lights stayed on while doors were open..... not the dome lights and other dash lights as they shut off as normal. Unfortunately the lights are still on. As reminder, they are only the ones on the steering wheel, all four door switches for the windows and locks, truck release and drive selector. I really appreciate you replying and trying to help.


So you are satisfied the driver's door latch switch is working correctly, that the dome light shuts off when the door closes.

I'll have to poke around some more looking at the schematics. I'll post back later with whatever I come up with.

Doug

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## 16.399981 (May 4, 2020)

plano-doug said:


> So you are satisfied the driver's door latch switch is working correctly, that the dome light shuts off when the door closes.
> 
> I'll have to poke around some more looking at the schematics. I'll post back later with whatever I come up with.
> 
> ...


Hi Doug.... Door latch switch seems fine and yes dome lights go off when doors are closed. Thanks for all the effort. You are certainly going above and beyond to help!


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## plano-doug (Jul 1, 2015)

LTZ RS 16 said:


> Hi Doug.... Door latch switch seems fine and yes dome lights go off when doors are closed. Thanks for all the effort. You are certainly going above and beyond to help!


To be clear, you use a key to turn off the ignition, right?

After running the car, when you shut the engine off and remove the key, what happens to the uncooperative lights when you adjust the dimmer switch by the headlight switch? Does it have any effect?

Looking at the schematics, I put the following list together. The BCM controls the lights listed, which I think matches up with what you listed. At the same time, the BCM also controls the dome lamp, albeit via a different fuse.
​Fuse F23 in the instrument panel fuse box feeds the BCM, which in turn feeds these:​o Door lock switch​o Headlamp switch​o Ignition mode switch​o Door lock switch - driver​o Transmission shift lever position indicator​o Steering wheel controls, left and right​o (+ several others)​​F32 (underhood fuse box) feeds the BCM which in turn feeds:​o dome lamp​o (+ several others)​​
Reading the description in the online Chilton's manual, the headlamp switch triggers the BCM to control the problematic lights. I'm still trying to understand better how this works, so I will avoid taking wild guesses at this point, and I hope it doesn't come to that 

Below is the Chilton's description:

With the headlamp switch in the PARK or HEAD position, the park lamp switch signal circuit provides an input to the body control module (BCM). The BCM responds by applying voltage to the park lamps as well as the backlight dimming control circuits illuminating all components with interior backlighting. All interior backlighting turns ON at the dimming level indicated by the instrument panel (I/P) dimmer switch. The I/P dimmer switch is a momentary type switch and utilizes a resistor ladder to increase and decrease the brightness of the interior backlighting components. The I/P dimmer switch provides a voltage signal to the BCM that will increase as the brightness of the lights are increased and decrease as the brightness of the lights are decreased. The BCM provides a low reference signal and a B+ circuit to the I/P dimmer switch. The BCM will only respond to the I/P dimmer switch when the ambient light sensor determines the outside lighting conditions are correct for night. When the I/P dimmer switch is held in the desired position, the dimmed voltage setting is applied from the I/P dimmer switch through the I/P dimmer switch signal circuit to the BCM. The BCM interprets the signal and applies a pulse width modulated (PWM) voltage through the backlighting control circuits illuminating the interior backlighting to the requested level of brightness.​
Anyway, for now, one thought I have is to pull fuse F23 when you get out of the car. At the least, that will keep your battery from dying.

One other thing is to play with the headlamp switch some more. Try switching into and out of the automatic mode to see if that has any effect.

Let me know what you find.

Doug










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## 16.399981 (May 4, 2020)

Hi Doug.... first of all thank you very much for all your time in this matter. This model is a push start/stop ignition. NO key. I will now read the rest of your reply as I wanted to let you know this first.


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## 16.399981 (May 4, 2020)

LTZ RS 16 said:


> Hi Doug.... first of all thank you very much for all your time in this matter. This model is a push start/stop ignition. NO key. I will now read the rest of your reply as I wanted to let you know this first.


Answer.... Dimmer swirch reduces the amount of glow but does not shut off the uncooperative lights. I have actually unpluged the light switch and it has no effect ... lights stay on. I was hoping it was as easy as a bad headlight switch. 
After running the car, when you shut the engine off and remove the key, what happens to the uncooperative lights when you adjust the dimmer switch by the headlight switch? Does it have any effect?


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## 16.399981 (May 4, 2020)

LTZ RS 16 said:


> Answer.... Dimmer switch reduces the amount of glow but does not shut off the uncooperative lights. I have actually unplugged the light switch and it has no effect ... lights stay on. I was hoping it was as easy as a bad headlight switch.
> After running the car, when you shut the engine off and remove the key, what happens to the uncooperative lights when you adjust the dimmer switch by the headlight switch? Does it have any effect?


Pulled F23 2A fuse.... uncooperative lights still stayed on even though fuse was out .... Start button/ trunk release shift indicator. Sorry. Also unplugged the headlight switch again and it had no effect on uncooperative lights.


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## plano-doug (Jul 1, 2015)

LTZ RS 16 said:


> Pulled F23 2A fuse.... uncooperative lights still stayed on even though fuse was out .... Start button/ trunk release shift indicator. Sorry. Also unplugged the headlight switch again and it had no effect on uncooperative lights.


To be clear, this was F23DA from the instrument panel fuse box - ie, DAsh fuse box, above the driver's left knee?

Also, earlier, did you try changing the headlamp mode from AUTO to manual (and back) to see if that had any effect after turning the car off?

I'm working off drawings for the 2015 Cruze. I don't have access to any for a 2016 Limited, but they should be the same. Still, there's always a chance something changed (even tho it's the same model).

I did find a drawing for the keyless ignition. Try pulling F3DA to see if that kills the lights.

Here's a list of all the fuses going into the BCM. (I can't believe F23DA didn't kill the lights )

BCM fuses:
F69UA 5A (UA means underhood fuse box)
F31UA 20A
F32UA 20A

F8DA 30A (DA means dash/instrument panel fuse box)
F9DA 30A
F3DA 25A <- try this one
F10DA 30A
F23DA 20A
F24DA 20A
F22DA 2A (ign sw)​
You might also try some of the others, such as F24DA.

I have a hard time believing the schematic is wrong, that F23DA didn't kill the lights. But then, maybe that's why they're staying on. Maybe there's a short somewhere keeping them on after the BCM turns them off. But, if the short is outside the BCM, that should preclude the dimmer from affecting the lights after key-off.

So that makes me think the BCM is wonky. I cannot 100% rule out a short/wiring issue outside the BCM, but given that the BCM controls the problem lights, and the dimming function works (after key-off), I'm thinking the problem is inside the BCM.

I'd much prefer to be diagnosing hands-on with test equipment rather than from my computer desk - I'd feel much more confident in my assessment. But for now, BCM is what I got.

From what I recall reading, you can get a BCM for around $100, plus another $200 to program it. Still, I would prefer to get a confirmation of bad BCM before dropping $300, probably at some additional cost. 

Doug

.


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## 16.399981 (May 4, 2020)

plano-doug said:


> To be clear, this was F23DA from the instrument panel fuse box - ie, DAsh fuse box, above the driver's left knee?
> 
> Also, earlier, did you try changing the headlamp mode from AUTO to manual (and back) to see if that had any effect after turning the car off?
> 
> ...


Hi Doug, Thanks for hanging in there with me. I had to step away for a little while. Yes under dash left knee area. F23 and the fuse has 20 on it. Yes I did move headlight mode from AUTO to MANUAL many times without luck. F3 does not kill the lights. Dimmer only works when car is turned on. Thanks for everything!


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## plano-doug (Jul 1, 2015)

LTZ RS 16 said:


> Hi Doug, Thanks for hanging in there with me. I had to step away for a little while. Yes under dash left knee area. F23 and the fuse has 20 on it. Yes I did move headlight mode from AUTO to MANUAL many times without luck. F3 does not kill the lights. Dimmer only works when car is turned on. Thanks for everything!


F3 was a shot in the dark. Just curious. Did you try any other fuses?

So, when you adjusted the lights with the dimmer, with the engine on, did the lights stay the same brightness once you turned the car off? I have read and re-read Chilton's description of how the dimming works, and the only thing clear is that the person who wrote it should be fired 

Seriously, it does say the BCM controls the uncooperative, dimmable lights. But it's not clear exactly how the dimmer switch and BCM interact. I couldn't find a drawing showing the dimmer switch, so I still have some questions about that. Regardless, I still think the BCM is the culprit, since it ultimately controls the malfunctioning lights.

Doug

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## 16.399981 (May 4, 2020)

plano-doug said:


> F3 was a shot in the dark. Just curious. Did you try any other fuses?
> 
> So, when you adjusted the lights with the dimmer, with the engine on, did the lights stay the same brightness once you turned the car off? I have read and re-read Chilton's description of how the dimming works, and the only thing clear is that the person who wrote it should be fired
> 
> ...


Good morning Doug......Answer: yes....lights stay same brightness once I turn off car. I will look into the BCM and keep you informed as to any new results that I come across in the future. I am determined to find out and correct this issue. Thank you for all your time and effort. You are centainly a dedicated and knowlegable person.
John


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## WillL84 (Aug 5, 2019)

Almost sounds like a flaky/bad BCM at this point


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## 16.399981 (May 4, 2020)

LTZ RS 16 said:


> Good morning Doug......Answer: yes....lights stay same brightness once I turn off car. I will look into the BCM and keep you informed as to any new results that I come across in the future. I am determined to find out and correct this issue. Thank you for all your time and effort. You are certainly a dedicated and knowledgeable person.
> John


Update.... checked fuses # 3 8 9 10 23 24 31 32 69 all related to BCM and look good.


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## 16.399981 (May 4, 2020)

Hi Doug....Took car to local chev dealer who has serviced it since new. Diagnosed as needing BCM 
Thanks again for all your help!


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## 16.399981 (May 4, 2020)

Snipesy said:


> Does the radio turn off when you open the door?
> 
> If not. Door switch. Eh just leave it.
> 
> If it does. Wiring harness or internal BCM failure.


Hello Snipesy, 
Took car to local chev dealer who has serviced it since new. Diagnosed as needing BCM 
Thanks for all your input!


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## 16.399981 (May 4, 2020)

WillL84 said:


> Almost sounds like a flaky/bad BCM at this point


WillL84 Took car to local chev dealer who has serviced it since new. Diagnosed as needing BCM 
Thanks for your input!


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## Blasirl (Mar 31, 2015)

So are you having the BCM replaced?


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## 16.399981 (May 4, 2020)

Blasirl said:


> So are you having the BCM replaced?


Yes... at the Chev dealer now. Dropped off Friday and they said it should be done tomorrow, (Monday 6/8/20)
Thanks for checking in.


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## Blasirl (Mar 31, 2015)

Keep us posted.


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