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Remote Keyless Entry Key Fob Failure and Repair
_______________________________
My remote keyless entry key fob control developed a mind of it's own.
Over time a spot on the key fob directly aside the smaller 'open' button had been pressed upon and worn down continually to the point where the key fob case became slightly cracked and depressed at that spot. A small groove ran radially outwards from the 'open' button for only a few millimeters long and about a millimeter deep. It appeared as a small thin V-shaped depression not unlike erosion from a thumbnail scratching the button in the same spot while actuating the 'open' command over many pressings.
Upon closer inspection, I'm assuming my above supposition was wrong. In reality, rather than a mere thumbnail rocking over on the remote door openings and eroding the highly durable plastic, the front of the case likely got grooved by being carried in pants pockets while walking about, with a key ring doubling over the key fob. An extra key ring attached to the one on the case of the fob was pressing on the edge of the 'open' button. In that position, a second key ring with house keys attached onto the first key ring directly attached to the fob, lined up exactly to the crack when twisted. The second key ring was pressing in that spot repeatedly with some levered force over time inadvertently causing the crack and depression visible from the outside. To prevent this inadvertent wear and tear on the remote keyless entry fob occurring again in the future, I'll simply keep the control in a looser location henceforth and remove some of the seldom used keys from the ring.
_______________________________
The result of that wear and tear on the key fob functionally was a keyless entry remote control that would actuate the 'open' signal repeatedly as I approached the car just by holding the case between the fingers with only the slightest pressure. Sometimes just taking the keys out of the pants pocket without touching the fob would cause the doors to open which initially was a cool feature, but that got old in short order.
The control was erratic: sometimes I didn't have to push the button as I approached the car but on other occasions pushing the 'open' button repeatedly was required to get it to function. Sometimes the door would already be open after I thought I locked it previously. Shaking the remote key fob in hand would sometimes open the door or stop the repeated clicking of the 'open' sequence.
When locking the vehicle it became necessary to exit the area around the car after locking the doors while holding the keys with the fob dangling in the air so as not to squeeze or even touch the case. Like some other electrical devices that have malfunctioned in the past, I was prone to give it a short sharp smack to rectify the situation and that ultimately worked to make it stop.
_______________________________
An internal short within the device was the obvious conclusion, especially upon seeing the small red signal light at the bottom of the key fob beside the 'lock' button actuate. This was first noticed when picking up the fob off a table in a darkened room. I assumed simply a lack of spring pressure on the backside of the 'open' button to be the main culprit and resolved to try and fix it vs. resorting to the pristine unused spare remote keyless entry fob that came with the vehicle and in testing worked perfectly.
_______________________________
To repair the malfunctioning remote entry control key fob versus replacing it didn't take much time at all.
The battery was removed with a large coin opening the cover at the back via a slight twist as per normal; next the key fob case itself was split open by easily prying the two halves apart with fingernails. Once the two halves were popped apart, revealed was the battery side of the small circuit board, set into a clear rubber gasket that fit snuggly into the front facing half of the key fob case holding the 'open', 'lock' and long red 'panic' button.
The gasket was easily pried out from the other half of the key fob case retaining the buttons, and the circuit board was then gently removed from the rubber gasket. In addition to sealing the sides of the key fob case, the rubber gasket also covered the circuit board on the side facing the buttons. The clear gasket slipped over the circuit not unlike a rubber shoe cover. It's main function seemed to be to make the device somewhat watertight and for dust protection and electrical insulation from the button side.
_______________________________
What the problem was within the device, could be seen in the button half of the case and on the circuit board itself.
An area of pushed in plastic shaped like a 'V', at the side of the small 'open' button on the inside of the case, was protruding down about a millimeter.
What was seen at the top as erosion of plastic was actually the section being force downward at a crack.
This protrusion downwards had displaced a flexible 'baby-moon' blister shaped metallic switch about the size of a pencil eraser end that was located underneath the 'open' button on the circuit board. That switch for the 'open' button was shorting to the actuating circuit directly with the slightest pressure on the case. The protrusion in the case itself had become the actuating button. Merely holding the case from the two sides without even any perceivable force was often enough to trip the circuit repeatedly.
Comparing it visually to the other blister-like metallic discs for the 'lock' and 'panic' switches also located under a small flexible strip of clear plastic over the circuit board revealed it to be a millimeter or thereabouts out of alignment. It was basically loose under the clear plastic and shifted.
The solution for the displacement was to simply push the small metallic blister-like switch for the 'open' control under the clear plastic strip, carefully with a finger nail back over into it's proper location similar to the other actuating buttons. There appeared to be a kind of round seat of the same diameter as the outside circumference of that small switch that it fit over to align properly.
Next was to flatten out the plastic case from the inside out with some delicate knocks with a suitable tool. For my weapon of choice, I used the rounded point of a welders hammer in multiple small well aimed taps on the inside of the plastic key fob case. I used a flat smooth piece of steel to back the front of the key fob case while tapping. This worked out great. The inside was tapped back in the the outside of the slightly cracked case was virtually flush again with not much of a readily visible depression.
Upon reassembly, care was taken to carefully seat the small thin and fine long tabs that locate the plastic buttons in position within the case. There are grooves and a pin to properly locate them. The gasket was snugged around the circuit board and pushed back again carefully into the front half of the case seated over the plastic buttons. The rear half of the key fob case was simply snapped on; a fresh Energizer CR2025 battery was installed, the battery enclosure cover was replaced and twisted closed again with a thick coin.
_______________________________
With the minute dent that was pushing into the circuit now removed from the inside out, and the internal metal blister-like switch budged back into it's proper location, there was happily good spring action once more upon the 'open' button. On actuation, the remote keyless entry fob worked perfectly as new, without any unwanted signals.
With a fresh battery installed at the time of the repair, hopefully all should be well for quite some time.
If this documentation of the repair is not clear, please let me know and I'll take some pictures. lolz.
_______________________________
My remote keyless entry key fob control developed a mind of it's own.
Over time a spot on the key fob directly aside the smaller 'open' button had been pressed upon and worn down continually to the point where the key fob case became slightly cracked and depressed at that spot. A small groove ran radially outwards from the 'open' button for only a few millimeters long and about a millimeter deep. It appeared as a small thin V-shaped depression not unlike erosion from a thumbnail scratching the button in the same spot while actuating the 'open' command over many pressings.
Upon closer inspection, I'm assuming my above supposition was wrong. In reality, rather than a mere thumbnail rocking over on the remote door openings and eroding the highly durable plastic, the front of the case likely got grooved by being carried in pants pockets while walking about, with a key ring doubling over the key fob. An extra key ring attached to the one on the case of the fob was pressing on the edge of the 'open' button. In that position, a second key ring with house keys attached onto the first key ring directly attached to the fob, lined up exactly to the crack when twisted. The second key ring was pressing in that spot repeatedly with some levered force over time inadvertently causing the crack and depression visible from the outside. To prevent this inadvertent wear and tear on the remote keyless entry fob occurring again in the future, I'll simply keep the control in a looser location henceforth and remove some of the seldom used keys from the ring.
_______________________________
The result of that wear and tear on the key fob functionally was a keyless entry remote control that would actuate the 'open' signal repeatedly as I approached the car just by holding the case between the fingers with only the slightest pressure. Sometimes just taking the keys out of the pants pocket without touching the fob would cause the doors to open which initially was a cool feature, but that got old in short order.
The control was erratic: sometimes I didn't have to push the button as I approached the car but on other occasions pushing the 'open' button repeatedly was required to get it to function. Sometimes the door would already be open after I thought I locked it previously. Shaking the remote key fob in hand would sometimes open the door or stop the repeated clicking of the 'open' sequence.
When locking the vehicle it became necessary to exit the area around the car after locking the doors while holding the keys with the fob dangling in the air so as not to squeeze or even touch the case. Like some other electrical devices that have malfunctioned in the past, I was prone to give it a short sharp smack to rectify the situation and that ultimately worked to make it stop.
_______________________________
An internal short within the device was the obvious conclusion, especially upon seeing the small red signal light at the bottom of the key fob beside the 'lock' button actuate. This was first noticed when picking up the fob off a table in a darkened room. I assumed simply a lack of spring pressure on the backside of the 'open' button to be the main culprit and resolved to try and fix it vs. resorting to the pristine unused spare remote keyless entry fob that came with the vehicle and in testing worked perfectly.
_______________________________
To repair the malfunctioning remote entry control key fob versus replacing it didn't take much time at all.
The battery was removed with a large coin opening the cover at the back via a slight twist as per normal; next the key fob case itself was split open by easily prying the two halves apart with fingernails. Once the two halves were popped apart, revealed was the battery side of the small circuit board, set into a clear rubber gasket that fit snuggly into the front facing half of the key fob case holding the 'open', 'lock' and long red 'panic' button.
The gasket was easily pried out from the other half of the key fob case retaining the buttons, and the circuit board was then gently removed from the rubber gasket. In addition to sealing the sides of the key fob case, the rubber gasket also covered the circuit board on the side facing the buttons. The clear gasket slipped over the circuit not unlike a rubber shoe cover. It's main function seemed to be to make the device somewhat watertight and for dust protection and electrical insulation from the button side.
_______________________________
What the problem was within the device, could be seen in the button half of the case and on the circuit board itself.
An area of pushed in plastic shaped like a 'V', at the side of the small 'open' button on the inside of the case, was protruding down about a millimeter.
What was seen at the top as erosion of plastic was actually the section being force downward at a crack.
This protrusion downwards had displaced a flexible 'baby-moon' blister shaped metallic switch about the size of a pencil eraser end that was located underneath the 'open' button on the circuit board. That switch for the 'open' button was shorting to the actuating circuit directly with the slightest pressure on the case. The protrusion in the case itself had become the actuating button. Merely holding the case from the two sides without even any perceivable force was often enough to trip the circuit repeatedly.
Comparing it visually to the other blister-like metallic discs for the 'lock' and 'panic' switches also located under a small flexible strip of clear plastic over the circuit board revealed it to be a millimeter or thereabouts out of alignment. It was basically loose under the clear plastic and shifted.
The solution for the displacement was to simply push the small metallic blister-like switch for the 'open' control under the clear plastic strip, carefully with a finger nail back over into it's proper location similar to the other actuating buttons. There appeared to be a kind of round seat of the same diameter as the outside circumference of that small switch that it fit over to align properly.
Next was to flatten out the plastic case from the inside out with some delicate knocks with a suitable tool. For my weapon of choice, I used the rounded point of a welders hammer in multiple small well aimed taps on the inside of the plastic key fob case. I used a flat smooth piece of steel to back the front of the key fob case while tapping. This worked out great. The inside was tapped back in the the outside of the slightly cracked case was virtually flush again with not much of a readily visible depression.
Upon reassembly, care was taken to carefully seat the small thin and fine long tabs that locate the plastic buttons in position within the case. There are grooves and a pin to properly locate them. The gasket was snugged around the circuit board and pushed back again carefully into the front half of the case seated over the plastic buttons. The rear half of the key fob case was simply snapped on; a fresh Energizer CR2025 battery was installed, the battery enclosure cover was replaced and twisted closed again with a thick coin.
_______________________________
With the minute dent that was pushing into the circuit now removed from the inside out, and the internal metal blister-like switch budged back into it's proper location, there was happily good spring action once more upon the 'open' button. On actuation, the remote keyless entry fob worked perfectly as new, without any unwanted signals.
With a fresh battery installed at the time of the repair, hopefully all should be well for quite some time.
If this documentation of the repair is not clear, please let me know and I'll take some pictures. lolz.
