Fried coil on trunk release

[Leghome]

As my son in-law and I were putting the dash back together after the new circuit board and LED's were installed in the dash we pinched the two wires that go to the trunk release button in the glove box. This pix shows what happens when you do that. Tom from Keyless Klassics has a new release on the way

 

[black07ss]

LarrE you must be careful. Every electric device comes with smoke installed in it, you must keep it in there because once you let it out it stops working

[MCfan]

Sorry for the mishap, Larry - shows what constant current can do to a solenoid that is only supposed to be momentarily pulsed.   You may actually be lucky that it didn't result in a fire or paint damage.

 

I suppose you could achieve the same result if you continued to mash on that release button or if the button stuck.  Your experience makes me glad that I told Tom about the first trunk release button that came in my kit because it was sticking in the engaged position rather than releasing when I removed finger pressure.   Tom cheerfully replaced the button for me and I've not had that problem since.

 

When you engage the trunk solenoid via the key fob, it receives only a momentary pulse from the receiver/controller so that should never be an exposure.  

 

Another interesting application is Power Seat Back Release systems which need to energize to disengage the seat back lock and hold it in that position for up to 20 seconds before dropping power.  The original factory systems used solenoids and Ford had a major problem with theirs, with at least five documented car fires attributed to overheated solenoids. GM's original system also used solenoids but features timed relays in the power circuit so they are safe.

 

Tom's Klassic Keyless seat back release system uses power door lock actuators with rack and motor-driven pinion instead of solenoids but they can also overheat unless they have overload protection (which Tom's do have).  I burned an unprotected actuator up after just 45 seconds when I was working on my prototype seat back release system.  Tom's production system also uses adjustable timer relays to limit the time the circuit is energized which avoids the problem.  I currently have mine set to release after 12 seconds but the little motors still get pretty warm.

[Leghome]

Received the new trunk latch Sat. Installed it this afternoon and it would not work. There was no power getting to the release. Called Tom at Keyless Klassics and he told me to clean up the contacts in the relay. He instructed me on how to open the relay up and what to use to clean them up. A small fine file cleaned the contacts, hooked everything back up and it now works flawlessly. Tom is a great guy to work with answers all questions without hesitation and makes suggestions on what might need to be done. He told me if cleaning the contacts did not work go an auto parts store and get a Bosch 5 terminal relay for about $5 and that would work.