Problem Moving from a Stop

[triangles]

First, I'm not nitpicking I'm just trying to help people understand how the FFE works.

The vehicle intermittently not having the transmission engage after backing out of a spot...

The FFE technically doesn't have a transmission. It has a gear box with a differential. It's a gear box and not a transmission because the gears are always connected to the motor. There are no "changing gears." When the car goes forward the motor spins one way and when the motor spins the other way the car backs up. So you see there's nothing to "engage" as the motor is always engaged with the wheels. That's why it should never be towed flat.

This article shows some cutaway images of the motor/gear box when the FFE was first shown to the public. http://www.electric-vehiclenews.com/201 ... posed.html The differential is inline with the motor and the passenger side axle actually goes thru the hollow center of the rotor. What you can't see in the pictures is the gear between the output of the motor and the differential. I'm not sure if it's been removed or just can't be seen in the pictures.

In my official internet expert opinion, I would guess only one of two things could be the problem if you can back out of a spot and then it won't go forward. 1) the switch that the mechanical "gear selector" is attached to is going bad such that the car doesn't know you've put it in D. 2) Something in the electronics of the inverter has gone bad. Ok so I just thought of a third possible but unlikely possibility, 3) the mechanical linkage between the shifter and the switch on the TCM is not right such that when you put the car in "D" the switch on the TCU isn't quite in the "D" position.

Sadly with the FFE's nonexistent data logging, if the problem is intermittent there's no way to troubleshoot what's wrong unless they just happen to catch it misbehaving when the diagnostic equipment is hooked up to the car. So they won't find the problem until it is no longer an intermittent problem. Good luck! Hopefully I'm just being a pessimist and they can figure it out with out just throwing parts at it or just telling you to go away, there's nothing wrong with it. Either way keep us updated.

[GHTech]

Quick Update:
The problem has not returned after the update 2 months ago. As the problem used to happen infrequently in the past, I am not celebrating yet. I just need it to behave for the next 11 months, until the lease expires. Will try to sell it off closer to the lease end, with about 17,000 miles (estimated) on it.

[carbuff]

I ran over a squirrel once.

[Anti_Climax]

I've had this happen before. I would back out, go into gear, stop at the store sign nearest my house and continue on. After stopping at the next stop sign I'd release the brake and the car would not move, even hitting the accelerator.

There's no question the car was fully started when this happened (and it happened enough times I took it into the dealer) but no cause was ever found.

I will say that I'm in the habit of going into drive pretty quickly after starting and I wonder if that may potentially cause a software issue of some kind. I've also occasionally encountered cogging in the motor, but shutting it off and starting again takes care of it.

The only other guess I've had would be the "creep" switch on the brake. If that were to get stuck in the engaged state the motor controller would turn off creep power and it would not move when taking your foot of the brake.

Might be a way to disable creep for those that don't want it, assuming it doesn't impact the rest of the drivetrain function.

[GHTech]

Hi!

I had the similar symptoms as you, and the TSB fixed it. The fix was applied in Apr. 2018, and the problem has not returned. I sold the FFE a week ago.

Regards,

GHTech

I've had this happen before. I would back out, go into gear, stop at the store sign nearest my house and continue on. After stopping at the next stop sign I'd release the brake and the car would not move, even hitting the accelerator.

[Anti_Climax]

I've had a couple re-occurrences of the cogging but not the stop behavior, so they may have fixed it and not even realized.

They haven't been super knowledgeable about it, so I would not be surprised if there was a behavior/fix that they didn't even associate with that service bulletin.