How to Convert 2006 Dimmer to Turn On Dome light
04-27-2007 | 11:22 AM
#21
Senior Member
Joined: 08-17-2006
Posts: 1,851
From: Ottawa, Ontario
Once again Steve, great how-to.
Thanks for the explanation of which BCM connector you selected to use and what would and would not happen when the dome light is turned on.
Is this how the 07s are wired?
Thanks for the explanation of which BCM connector you selected to use and what would and would not happen when the dome light is turned on.
Is this how the 07s are wired?
04-27-2007 | 06:59 PM
#22
Senior Member
Joined: 04-30-2006
Posts: 9,149
From: Maryland Heights, MO
The next how-to will be converting the outside mirrors to heated mirrors. I have all the parts here (heater elements and replacement glass pieces). It will be wired to operate whenever the rear defroster is on (like my other GM vehicles). Since winter is over (hopefully) I won't need heated mirrors until next winter, so the priority is low on my list right now. Some time over the summer I will do the conversion and will post a similar how-to for that.
Steve
Steve
04-27-2007 | 10:25 PM
#23
Senior Member
Joined: 09-12-2005
Posts: 317
From: Parkland (Tacoma), WA
OOps! forgot to answer crazybob's question. No, the car doesn't think that the door is open when I turn on the dome light. I specifically picked the BCM connection that wouldn't do that. The normal way for the dome light to come on is when the door switches indicate a door is open. The door switches are inputs to the BCM, which then grounds terminal A10 on the BCM to turn on the dome lights. Had I wired the dimmer switch to a door switch input on the BCM, then there would be a "door open" indication on the DIC. The way I wired the dimmers switch, it manually grounds the dome lights to turn them on. The BCM actually never knows that you have turned them on manually.
Also, the + power circuit for the dome lights is controlled by the BCM, so even if you turn them on manually with the dimmer switch, the battery-saving feature that turns off the interior lights 15min after turning off the ignition should still work.
Steve
Also, the + power circuit for the dome lights is controlled by the BCM, so even if you turn them on manually with the dimmer switch, the battery-saving feature that turns off the interior lights 15min after turning off the ignition should still work.
Steve
04-29-2007 | 10:08 PM
#25
Senior Member
Joined: 09-12-2005
Posts: 317
From: Parkland (Tacoma), WA
Just go to Radio Shack and get a 1A (Probably overkill) diode. Cut the wire (A10) going to the BCM. Place the diode inline with the stripe pointing away from the BCM. On the Stripe side of the diode, also connect the wire from the new switch that you just added. You can use crimp connectors for this but I recommend solder. Tape or shrink tube all connections. Maybe this diagram will help. The dots indicate where the connections are made.
04-30-2007 | 08:18 AM
#26
Thread Starter
Senior Member
Joined: 02-01-2006
Posts: 1,421
From: lockport,ny
Crazybob:
In the diode configuration that you show in the picture, wouldn't that prevent the BCM from grounding the line, therefore the lights would cease to be under ECM control? For normal BCM control the current flows thru the dome lights and into the BCM, which grounds the line to complete the path.
I agree that some isolation would be a good idea. Trying to figure out what to do without disrupting normal operation is the key.
Since my additional connection is only to ground, voltage could never be applied externally to the BCM pin. Therefore the only consideration seems to be that the BCM could have some voltage on the pin when it's not turning the dome lights on and if you ground it externally, there could be some current flow which could damage the BCM. In that case, the diode should be turned the other way, which would allow current flow into the pin (so the BCM could turn on the dome lights) but prevent flow out of the pin into the new external ground.
What is your opinion on my comments? I'm writing this early in the morning, so maybe the coffee hasn't taken effect yet.
Steve
In the diode configuration that you show in the picture, wouldn't that prevent the BCM from grounding the line, therefore the lights would cease to be under ECM control? For normal BCM control the current flows thru the dome lights and into the BCM, which grounds the line to complete the path.
I agree that some isolation would be a good idea. Trying to figure out what to do without disrupting normal operation is the key.
Since my additional connection is only to ground, voltage could never be applied externally to the BCM pin. Therefore the only consideration seems to be that the BCM could have some voltage on the pin when it's not turning the dome lights on and if you ground it externally, there could be some current flow which could damage the BCM. In that case, the diode should be turned the other way, which would allow current flow into the pin (so the BCM could turn on the dome lights) but prevent flow out of the pin into the new external ground.
What is your opinion on my comments? I'm writing this early in the morning, so maybe the coffee hasn't taken effect yet.
Steve
05-01-2007 | 12:01 AM
#28
Senior Member
Joined: 09-12-2005
Posts: 317
From: Parkland (Tacoma), WA
Crazybob:
In the diode configuration that you show in the picture, wouldn't that prevent the BCM from grounding the line, therefore the lights would cease to be under ECM control? For normal BCM control the current flows thru the dome lights and into the BCM, which grounds the line to complete the path.
I agree that some isolation would be a good idea. Trying to figure out what to do without disrupting normal operation is the key.
Since my additional connection is only to ground, voltage could never be applied externally to the BCM pin. Therefore the only consideration seems to be that the BCM could have some voltage on the pin when it's not turning the dome lights on and if you ground it externally, there could be some current flow which could damage the BCM. In that case, the diode should be turned the other way, which would allow current flow into the pin (so the BCM could turn on the dome lights) but prevent flow out of the pin into the new external ground.
What is your opinion on my comments? I'm writing this early in the morning, so maybe the coffee hasn't taken effect yet.
Steve
In the diode configuration that you show in the picture, wouldn't that prevent the BCM from grounding the line, therefore the lights would cease to be under ECM control? For normal BCM control the current flows thru the dome lights and into the BCM, which grounds the line to complete the path.
I agree that some isolation would be a good idea. Trying to figure out what to do without disrupting normal operation is the key.
Since my additional connection is only to ground, voltage could never be applied externally to the BCM pin. Therefore the only consideration seems to be that the BCM could have some voltage on the pin when it's not turning the dome lights on and if you ground it externally, there could be some current flow which could damage the BCM. In that case, the diode should be turned the other way, which would allow current flow into the pin (so the BCM could turn on the dome lights) but prevent flow out of the pin into the new external ground.
What is your opinion on my comments? I'm writing this early in the morning, so maybe the coffee hasn't taken effect yet.
Steve
Never assume that because a wire is "just for ground" that it's not as dangerous as a power wire in terms of back-feeding damaging something. I learned this the hard way on a Subaru Legacy one time when I installed an alarm in it. I popped a $200 computer whose sole job was to turn on the freakin' domelight! All because I didn't use an isolation diode.
05-07-2007 | 11:50 AM
#29
Joined: 05-26-2006
Posts: 9
From: Illinois
Terminal part numbers
Hey everyone. Just to let you know, your local gm dealer should have these terminals. They are in the terminal repair kit that we all get ( I work for a chevy dealer). The part number is 12040511 as posted earlier. Tell your parts guy that they are in tray number 3 of the Delphi automotive kit. I spent the a whole month organizing these at my dealership, so I knew where they where at. This is what GM calls an "Essential" tool, so all gm shops are required to have them. If they try and tell you they don't have this kit, it's probably because they haven't organized it yet. Trust me, it's a giant pain in the backside.
05-07-2007 | 01:27 PM
#30
Senior Member
Joined: 04-30-2006
Posts: 9,149
From: Maryland Heights, MO
Hey everyone. Just to let you know, your local gm dealer should have these terminals. They are in the terminal repair kit that we all get ( I work for a chevy dealer). The part number is 12040511 as posted earlier. Tell your parts guy that they are in tray number 3 of the Delphi automotive kit. I spent the a whole month organizing these at my dealership, so I knew where they where at. This is what GM calls an "Essential" tool, so all gm shops are required to have them. If they try and tell you they don't have this kit, it's probably because they haven't organized it yet. Trust me, it's a giant pain in the backside.