Ok, one more way to test if you’re up to it.
Check to se if you have an rms voltmeter.
Check a 9 volt battery on the dc scale.
Then put it on ac, should read close to zero. Meaning it only reads ac rms voltage.
You can then check for data activity between B- and pin 23.
Should read around 3.6 vac.
Only works with a good meter that reads “ac only” on ac setting.
ps.
I may be wasting your time. 
OK I will give that a try tomorrow. I believe I have the correct voltmeter.
I checked ac voltage at p23 with key on and black lead at b- and 0v…dead.
Down to three things then.
Controller bad
Wire 23 shorted to B-
Control board input shorted to B-
Gotcha. So based on my visual inspection of the corrosion inside controller I need to send that to Rodney for rebuilding.
How do I get in touch with him?
My guess is he is Old Houseboater.
Yes, pm old houseboater if he doesn’t see this.
He may have other ideas.
He has a T3 that’s good but is looking to upgrade.
As a follow up to the original problem of no go and flashing icons on dash.
It turned out to be the controller. After taking it apart there were visible signs of water damage and corrosion because the unit was not completely waterproof. After several suggestions by Rodney we came to the conclusion that it needed to be rebuilt. I sent it to him and got it back less than 3 weeks later and it was plug and play. No issues.
If anyone is experiencing issues like mine message me and I will try to walk you through steps to determine whether it is the controller or not.
Thanks
Thank you for getting back to us with your results… Many come here asking for help and few report back with the results.
Right on.:thumb::thumb:
Where did you send your controller to get rebuilt? I have the exact same problem described in this thread. Thanks.
Hey there
I sent the controller to Rodney Diehl in Florida, he has a local company that rebuilds the units. He is in the forum as OLD HOUSEBOATER
I am having the same problem. how much did he charge you?
I had the Temp on my Dash. Car would not go over 5mph. It was the the fact that I didn’t have the temp sense plugged in.
What is pin #23 can you take a picture this same thing happened to me where my headlights were out and once I finally got it fixed test drove it parked it 2 days later the mechanic wrench showed up and it says it’s going 15 MPH sitting still
What is pin #23 can you take a picture this same thing happened to me where my headlights were out and once I finally got it fixed test drove it parked it 2 days later the mechanic wrench showed up and it says it’s going 15 MPH sitting still
The factory GE motor has a Temp sense on it. It needs to be connected so either that is not hooked up or your car is in a code -41 controller overheat error check the motor connection and let us know. Here is what your looking for. It’s the Black 2 Wire connector I’m pointing at
Correction. WHen the LCD is not flashing I get 77v on 1,2,4,10,17,21. I still do not get 12v on 15 or 5v on 9. When its flashing I get what I stated below.
New here…but have been struggling with a 2012 GEM T4 controller. I’ve been through all the wiring and all seems to be correct. The main contactor does not engage when i turn the key on. And I get the flashing LCD screen sporadically. I get no codes. I checked B+ on Pin1 and get 0. I also do not get 12v on pin15 or 5v on Pin9. I noticed where you said this could be an easier fix. Could you let me know what that fix is? Thanks!
I have seen the “crazy” screen several times, it has always turned out to be a loose connection. Most of the time unplugging, checking and re-plugging the controller harness corrects my issue.
The factory ignition (key) switch is not very robust. I had intermittent electrical problems with my 2014 that I couldn’t trace out. Ended up replacing the key switch. No more problems. Napa is much cheaper ($21) than factory ($150). I needed the switch with screw on terminals due to space issues. Simple wire terminal change and works like a charm.
