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Key Fob Detection Issue - Tesla Blames Weak Battery & Dashcam

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Just had my car in for its annual service and other minor problems to be addressed. Among them I stated that while key was with person in drivers seat and the car was in the unlocked status for doors the handles would randomly present themselves. Tesla noted it was possibly due to the weak key fob battery and/or my dashcam (blackvue 650). Has anyone had issues with key detection while using a dashcam or had similar issues caused by a dashcam?


Concern: Customer states: All door handles present randomly when key is in the car.

Corrections: Exterior Door Handles General Diagnosis

Tested concern and was unable to duplicate at service. Reviewed logs and found error reading of key sense antenna. Performed antenna test and confirmed correct operation. Per toolbox article, Aftermarket brand equipped dashcam is known to cause issues with Model S key detection. Suspect weak key batteries and interference from dashcam are cause of handle behavior. Replaced both key batteries at this time. Recommend removal of Aftermarket dashcam to allow system to operate normally.
 
I recall someone having problems after installing dash cam. I thought it was crimped wire or something. May be dreaming, cannot find any references by searching forum.
I also recall reading this on the forum, basically he or his installer had cut the wire for the rear camera and attached a new connector to the end. I think it was to shorten or to fish the wire through the rear, either way the cable was generating enough interference to disrupt the key Fob. To test this you could try disconnecting the rear camera cable from the dash cam and see if you still have issues. If not I'd suggest replacing the cable and not cutting the ends to solve the problem.
 
I also recall reading this on the forum, basically he or his installer had cut the wire for the rear camera and attached a new connector to the end. I think it was to shorten or to fish the wire through the rear, either way the cable was generating enough interference to disrupt the key Fob. To test this you could try disconnecting the rear camera cable from the dash cam and see if you still have issues. If not I'd suggest replacing the cable and not cutting the ends to solve the problem.

I will try this, thank you for suggestions.
 
I think it was Teslatap that posted a warning about where we should or should not run the rear dashcam cable. I think it was Teslatap.
What's important is - do not run the rear camera cable on the left side of the liftgate lid. The rubber grommet on the left side holds the various antenna leads for the rear of the car. For instance, this left side includes the fob antenna lead for the trunk antenna. The trunk fob antenna is mounted behind the bumper cover on the frame just about where the actual latch/lock is. But the wire/antenna lead runs from there along the inside of the car.

According to Teslatap, the rear dashcam cable/lead must be run through the right hand/passenger side. Where is your 650's rear camera cable your run? Is it on the right side?
 
I would believe a weak fob battery, though I'm supprised the fob wasnt opened and battery tested. Other brands have known issues with not sensing the fobs in the vehicle. A partly flat battery only make the issue easier to reproduce. I saw open the fob, anything under 2.9 volts replace the battery. Also is it happening with both fobs?
 
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I saw open the fob, anything under 2.9 volts replace the battery. Also is it happening with both fobs?

SInce the annual service was performed at the same time as the troubleshooting the batteries were replaced in both fobs.

According to Teslatap, the rear dashcam cable/lead must be run through the right hand/passenger side. Where is your 650's rear camera cable your run? Is it on the right side?

The install of the camera was done by the clear bra installer, I will need to ask him. Thank you!
 
About a year ago BlackVue realized that the cable they supplied to feed the rear facing camera was poorly insulated. In addition some installers (which was true in my case) would cut the cable in order to shorten it and re-solder the connector. Both the poor insulation of the original cable and the re-soldering introduced spurious radiation. That caused multiple problems: erratic key sensing, off setting of the GPS indicator on the map (the car would track off of the indicated route by a few feet to as much as a few miles) and other bad stuff. Since then they have supplied a much better insulated cable and recommended not to cut or shorten that cable.

Using the new, unmodified cable solved my problems both with the key sensing and with the GPS tracking.....

Just my personal experience.