[FackDaddy]

Hey y’all!
Love this forum btw!
So the horn is inop but somehow works when you press the trunk release? The auto trunk only latches and pulls down while pressing the yellow trunk release in the glove box.
Any ideas?

 

[scottelderado]

Hi FD, I'm rusty on this stuff, so buyer beware. Maybe those things are on the same circuit, but the horn/trunk isn't grounding unless the button in the glove box does the grounding? Basically, I think you should find an electrical diagram and check/clean the grounds. If not obvious, get a multimeter and start checking things. Others please correct me.

 

[1979 Eldorado]

Assuming things are the same on a car without auto-pulldown the ground for the trunk popper is through the mounting of the popper, part attached to the trunk lid, as I recall. There is a single power wire running to the glove box yellow button. The button is a normally-open switch that closes when you push it and a single wire goes to the solenoid on the trunk popper. I believe the factory wiring only allowed the popper to function with the key in to better secure the trunk if someone broke into your car. When I added it to a car I used a source which was hot all of the time.

Power will find a ground in strange ways if the ground is bad. Maybe things are on the same circuit and there's a bad ground which is causing the power to take an alternative path to find ground.

Also be careful going solely by a multimeter as you have no load when you check voltage. If it's a bad ground you may want to also have an "old school" test light with an incandescent bulb as your load.

Scott

 

[FackDaddy]

Assuming things are the same on a car without auto-pulldown the ground for the trunk popper is through the mounting of the popper, part attached to the trunk lid, as I recall. There is a single power wire running to the glove box yellow button. The button is a normally-open switch that closes when you push it and a single wire goes to the solenoid on the trunk popper. I believe the factory wiring only allowed the popper to function with the key in to better secure the trunk if someone broke into your car. When I added it to a car I used a source which was hot all of the time.

Power will find a ground in strange ways if the ground is bad. Maybe things are on the same circuit and there's a bad ground which is causing the power to take an alternative path to find ground.

Also be careful going solely by a multimeter as you have no load when you check voltage. If it's a bad ground you may want to also have an "old school" test light with an incandescent bulb as your load.

Scott

Thanks Scott!
I will check. It does have the auto pull down on the trunk lid. The scene of me at a gas station with my kid pressing the button multiple times with the horn honking and me desperately trying to get the trunk to latch was hilarious 😆

 

[1979 Eldorado]

I can imagine! Good thing you brought the kid. On the bright side that's an experience which will likely be a memory for a long time

I only mentioned my experience was without the pulldown because they may have needed to integrate the wiring on the version with the pulldown else each time the popper released the trunk the pulldown may want to close it again. I planned to work on a replacement pulldown switch at some point but on the smashed one I have for reference one of the contact straps is missing. They are more complicated than some people would think as they need to know when NOT to work.

Scott