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Help! Help with trunk lights

05 GRAND DADDY

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2005 Light Platinium Silver XLR
Started getting Roxy ready for Springtime rolling, when i noticed very dim lights in the 2 side trunk lights! I seem to have a low voltage reading with a volt meter, but not enough to light the regular factory bulbs at all, but it is enough power to light an LED replacement bulb, just very dim, in the only 2 back side lights. I added some extra LED’s to help light up the trunk area a few years a go and they worked fine last year up to now. All the other interior lights in cabin, door ect.... are working fine! Almost seem to be a ground situation. I unhooked all new added LEDS and problem is still there! Any help with solutions to try would be well appreciated. Thanks


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long Tall Sally

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Aiken SC
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2008 xlr dove gray
some led bulbs will only burn connected one way. you might be getting a feedback to make them burn dim if they are peanut bulbs try rotating them. I have seen that make the mbrighter. Also could be the bod yground wire on the frame at the rear behind the wheel. That sounds like the start of a loss of ground if your battery is fully charged.
 

05 GRAND DADDY

Seasoned Member
Joined
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Messages
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Location
South Central PA (Littlestown)
My XLR/V(s)
2005 Light Platinium Silver XLR
some led bulbs will only burn connected one way. you might be getting a feedback to make them burn dim if they are peanut bulbs try rotating them. I have seen that make the mbrighter. Also could be the bod yground wire on the frame at the rear behind the wheel. That sounds like the start of a loss of ground if your battery is fully charged.

Yea I know about LED’s fitting in only one way on some bulbs, but like mentioned the regular oem bulbs will not light. I’ll check that body ground today. Is that on drivers or passengers side do you recall? Thanks
 

IAN

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2004 silver XLR
6   Harness for instruments 0508236Y02-005[1].jpgHY GRAND DADDY.

Hi have the same problem on an intermitant time, it could very well be the ground, find enclosed a photo showing the interior wiring.

IAN
 

05 GRAND DADDY

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2005 Light Platinium Silver XLR
View attachment 8683HY GRAND DADDY.

Hi have the same problem on an intermitant time, it could very well be the ground, find enclosed a photo showing the interior wiring.

IAN

No luck with the ground wire behind drivers side rear tire, pulled off, cleaned with wire brush dermal tool and reinstalled, made no difference.


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IAN

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Province of Québec
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2004 silver XLR
Then whith a light tool, check the ground wire it self connecting from this cleaned area and the rear compartment light bulb, the wire could be pinched or else and not getting the ground working perfectly.

IAN
 

long Tall Sally

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2008 xlr dove gray
that ground does cause several problems so yo udid nto waste your time. There is also one on the passenger side if I remember correctly. Iwill look to see its location
 

05 GRAND DADDY

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2005 Light Platinium Silver XLR
that ground does cause several problems so yo udid nto waste your time. There is also one on the passenger side if I remember correctly. Iwill look to see its location

I Will check that tomorrow


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IAN

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2004 silver XLR
HI GD.

Since it seems that it is not the ground wires. 301

The trunk lights are part of all the courtesy lamps circuit, such as for the floor, the consol, the glove compartment, the hood interior, the doors, the mirror lamps/reading lamps and including the trunk compartment. ( cool to know )

On cloudy days and night they will work perfectly…..on bright sunny day the power is reduced to all most nothing, there is no switch for it, as is is controlled by the trunk lid opening actuator ( white and black wire….

The courtesy lamps power is connected directly to the battery and after 19 seconds they should come off, when they are on full power in the proper circonstances.

Their ground are 202 at the A post area and 302 at the B post area of the RH side of the car. ( cool to know )

Best time to test the lamps are on the end of the day, while the sun is gone or almost.

Good Luck.

IAN
 

05 GRAND DADDY

Seasoned Member
Joined
Jun 17, 2011
Messages
2,758
Location
South Central PA (Littlestown)
My XLR/V(s)
2005 Light Platinium Silver XLR
HI GD.

Since it seems that it is not the ground wires. 301

The trunk lights are part of all the courtesy lamps circuit, such as for the floor, the consol, the glove compartment, the hood interior, the doors, the mirror lamps/reading lamps and including the trunk compartment. ( cool to know )

On cloudy days and night they will work perfectly…..on bright sunny day the power is reduced to all most nothing, there is no switch for it, as is is controlled by the trunk lid opening actuator ( white and black wire….

The courtesy lamps power is connected directly to the battery and after 19 seconds they should come off, when they are on full power in the proper circonstances.

Their ground are 202 at the A post area and 302 at the B post area of the RH side of the car. ( cool to know )

Best time to test the lamps are on the end of the day, while the sun is gone or almost.

Good Luck.

IAN

So if I’m reading this correctly, the light from the amount of daylight that’s surrounding the car. Any idea where the dimmer sensor is at, so that it could be blocked, of daylight, to trick the sensor into make it respond as it’s like nighttime darkness? That would make sense because when I worked on it before the car was in my garage attached to our home with very little exterior light, but it’s now parked in the new garage where there is more windows leaving in more sunlight! I need to check it when it’s dark in the building! Also do you happen to know where the light switch is located that operates those trunks lights when the trunk opens and closes? Thanks


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IAN

Seasoned Member
Joined
Feb 19, 2015
Messages
496
Location
Province of Québec
My XLR/V(s)
2004 silver XLR
Hi G D.

It is a wiring circuit for all courtesy lamps that works together or individually.

GM has figure out….. if its a sunny and a clear day, you dont needs the courtesy lamps…..its perhaps one way to see the needs.

There is no censors at all.….there is a ''trunk lamp control '' witch is included into the rear deck lid latch actuator….but no switch or censor that i could find.

Myself i was confused with those weak lamps, i got to know their way of working ,when i was reading my owner manual lately and my repair manual, it happened that we see easely those weak trunk lamps , but all the other are also weak or close, we just dont happened to see them on a clear sunny day.

You could have some led strip lamps installed on the cigarette lighter wiring circuit with a switch it could be the solution for your needs.

IAN
 

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