I read an earlier post on this code. My GEM quits but will go in reverse. Was not sure from reading this post if the controller fixed the problem or new contacts. If someone could direct me to a correct fix it would be greatly appreciated.
A field transistor is shorted in the controller.
A fairly easy fix as far as controller problems go.
INWO can fix this problem. Look up Omni Electronics Hokah Minnesota
Rodney
Do you mind explaining to me in layman terms what I need to buy and how to fix. Thank you
A part inside the controller is bad.
There are 2 for forward and 2 for reverse. They route power to the motor field, telling motor which way to spin.
Controller will have to be removed.
If you know someone handy with electronic repair, I will take him/her through it.
Rodney can send it in for rebuild with a warranty.
I can repair it for $150. No fix-no charge. Only a part replacement, not a rebuild and no warranty.
Can you send me your information. Thank you for your help.
Intermittent.
Rodney, can brushes or motor problem throw code 66?
When field transistors go, usually short completely.
I hate for him to waste his time.
How much is the controller rebuild?
Don’t think so or there would be a ton more 66 failures
I got $368 for controller rebuild back to stock with zero miles. Not doing it anymore. Only do motors now.
Got the controller today.
It has a 1-3-18 rebuild date.
I don’t want to dig into this. Why don’t you get an ra from FSIP and I’ll forward it for you.
Dave
I am not understanding what you mean. Ra from FSIP. Also why don’t you want to tear into it. It is not working properly as it is. Just wondering your thought process.
Thanks
Lonnie
I will tear into it, but it will void your warranty, and I can’t guaranty a repair.
Won’t know until, I open it up.
Is there a reason that you don’t think it is warranted?
Ra=return authorization.
FSIP is the rebuilder.
My thought process=slow. 
The guys who worked on it won’t do anything. They said if I send it in and it did not have a problem that it would cost me at least $500. I am thru dealing with them. I spent over $2900 and when I got it back it still didn’t run. So please gave at it.
Thanks
Lonnie
Ok, I wasn’t aware of the no problem found cost.
I’ll take a look at it.
It definitely has serious issues.
It sucks to be you. 
You have been hosed, and I don’t know what to do without making things worse.
Half of the solder joints are poorly done.
Rodney might owe me a small favor. The only guy I know that might have their ear.
If I start butchering, no one will touch it again.
Between the field transistors and armature transistor 102 solder points.
They will not accept solder due to the plastic coating applied to the pads after assembly.
All will have to be desoldered, cleaned and redone.
This is way over my ability to get right in one shot. And no way to test properly. Although I will have to say, the smallest measure of quality control would have put this one in the trash.
Let me see if it shows in a picture. My camera is as old as I am.
First picture is the first suspect pin I found. Red.
Notice my solder balled up. It will not flow down through plated hole as it should.
2nd picture is bottom of same pin. #1 F.
If it was mine and it was given to me. I’d take all the time needed to completely disassemble, clean, re-solder, and test.
I can’t do it properly for cost of a rebuild.
Now if I was the guy with the $2900 in my pocket, we could talk. 
Remember, 102 connections.
If you show them this, they will tell you, I’m an ■■■■■ and invalidated the warranty. And maybe they would be right.
Any ideas from your end?
Sorry to rub salt in your wound. It won’t help if I cry!
Let me know what needs to be done. I’m not shocked or surprised at this point.
I’m at a loss.
Of course this is only my opinion. I have no support from the manufacturer.
I don’t see any way we can walk away on friendly terms. Although, I like to help when I can, my real job is $100 an hour.
Do you have a friend in the electronic biz? Tv repair or such.
Not such a technical repair, but time consuming.
So far, no charge on this end…
No I have no ideas. Did I read earlier that someone you know had a rebuild for sale or am I dreaming?
Thanks
No, I thought about sending you one to test. It may only cause you more grief.
I have one of Grants here that I never found the time to test.
If you tried it and it fixed your issue great. But if it didn’t work we would learn nothing, as it has a questionable history.
I don’t want to dig a bigger hole for you.
I’m sure your time is valuable also.
Mike, do you have one for sale?