Releasing the front/rear wheels with no power or blown pyro fuse

[rrolsbe]

On a rear wheel drive unit the front wheels should freewheel if jacked up? Do the front wheels freewheel on an all wheel drive if jacked up (I think they should)? Neither has a parking brake on the front wheels? If you unplug the connectors to the electric parking brake on both sides and apply 12VDC, do the brakes stay retracted after removing the 12V source?

If the pyro fuse is blown and you still have 12V power can you put the car in tow mode via the center screen? With the pyro fuse blown the DC-to-DC 12V converter could not supply 12V; therefore, if you removed the 12V battery negative terminal, would the car remain in tow mode (parking brake released)? Normally the car exits tow mode and sets the electric parking brake after 10 minutes. If the car does remain in tow mode, I guess you could temporarily connect a jump starter across the 12V battery terminals even if the 12V was removed/disconnected.

Maybe someone has done or should do a Youtube video on how to move a bricked Tesla car without a tow truck flat bed.

Thanks in advance for confirming any of the above. Please correct anything in error and add additional info as necessary.

 

[jjrandorin]

Maybe someone has done or should do a Youtube video on how to move a bricked Tesla car without a tow truck flat bed.

I dont know a thing about all the other things you asked, but you could move the car the same way that parking lot attendants move cars they cant get into. Wheel dollies:

 

[gearchruncher]

On a rear wheel drive unit the front wheels should freewheel if jacked up? Do the front wheels freewheel on an all wheel drive if jacked up (I think they should)? Neither has a parking brake on the front wheels? If you unplug the connectors to the electric parking brake on both sides and apply 12VDC, do the brakes stay retracted after removing the 12V source?

Front Axle has no parking brake or pawl or anything else. Wheels freewheel unless the hydraulic brake pressure is applied. This is true with AWD or RWD (unless the AWD drive unit is messed up). I know for a fact on an AWD with the HV contactor disconnected that you can spin the front wheels easily.

Rear axle has electric parking brake. This is bi-stable- it stays in the position it's in until power is applied. If the parking brake is not engaged, you can unplug the connectors and it will stay disengaged. It takes 12V to move it from engaged to disengaged and vice versa. Same thing here- these wheels spin freely if the parking brake and hydraulic brake are not applied. FYI, you can use a 9V battery and some alligator clips to disengage the parking brake. You can also just unscrew the parking brake motor from the back of the caliper and this will free the brakes.

I know the parking brakes run on 12V, so I do believe that if you hook a 12V jumper to the whole car, boot it, and put it in tow mode then kill the power, they will stay disengaged. No good reason I know of that Tesla would block tow mode just because the HV circuit is not on, but I haven't tried that specific thing.

 

[rrolsbe]

Thanks for reply and great information!

 

[Gauss Guzzler]

@gearchruncher is correct.

By the way, be extra careful when stealing Teslas. The car will radio in the GPS coordinates of your chop shop if you don't know what you're doing.

 

[jayfrank]

the parking brakes run on 12V, so I do believe that if you hook a 12V jumper to the whole car, boot it, and put it in tow mode then kill the power, they will stay disengaged. No good reason I know of that Tesla would block tow mode just because the HV circuit is not on, but I haven't tried that specific thing.

This is correct. I recently had to go through a lot to car towable. The pyro fuse and 12V battery both died within about 10 minutes of each other. I had to use a 12V battery to open the front trunk. I used the backup battery from my home alarm system. You open the tow area and pull out the two wires, connect the battery to them and the frunk opens up. Once that is open, I could jump the 12V battery to enable the doors and center screen. It will take about three minutes to boot up. Once booted, enable tow mode. Make sure you have something in front of the wheels if you're on a hill! Once in tow mode, I would roll down the driver window a hair so you don't mess up the seal. Then you can remove the other car from the equation. The car will die again, but at least it will be in tow mode and should move freely. Also, make sure you don't have the parking brake applied while the computer is still functional.

Hope that helps.

 

[Tayne]

I am having issues getting mine into towing mode. I connect the 12v the front computer comes on. The tow option is greyed out. The high voltage will not connect. Driver side doors work but passenger side will not. It was working but did a software update that failed. Now the high voltage will not engage. Any ideas would be helpful. I have unplugged the 12v from the penthouse and the negative from the 12v battery and rebooted several times, but doesn’t work.

 

[Tayne]

So I took the rear tires off. I disconnected the power to the parking brake motors. Then connected wires to the terminals. With jumper cables it powered the motor. Swapping the neg/pos if the caliper didn’t loosen. Till the wheels could move. I left them disconnected and put the tires back on. Now it can be moved.