I am relatively new to GEMs but in my short time I have enjoyed getting to work on them. I have one that came into my shop that has had me stumped for a little bit so I am reaching out for some help.
Its a 2012 e4 with no movement. There have been several issues that I found and fixed like the parking switch, a ground issue, and a loose wire on the contactor, but still no movement.
I am assuming that the pedal is an issue: When I check my voltages on the 23 pin for the pedal my 5V reference goes from 4.8V with pedal unplugged to 3.0V with it plugged in. My wiper is stuck at 0.1V. So I am assuming that is my main problem but I want to keep the repair cost effective and dont want to throw parts at it without being sure.
I also have an issue when I plug in the 12V dc dc converter I am getting 72V on my chassis ground. I tried to verify it is a phantom voltage but even with a 10kohm resistor there, I was getting 72V.
I have also created a harness that allows me to breakout the 23 pin connector without having to backprobe and I have not been able to get my sentry to MONITOR. I can read (and i am assuming i have the ability to download) parameters but I cannot get monitor to work. With key off, no signal, with key on I have a signal but no live readings.
What is the history of this car? Has it been worked on recently?
Check controller model. I believe that a 2012 needs to be a T5 and throttle is hall effect type. Hall throttles need at least 4.5v to function. Pin #9.
Monitor does not work properly with controllers above T2. To connect monitor. Disconnect pin 2 and 17. When prompted for key on. Connect P2. Not sure about p17 if not connected to MC coil. If in car, reconnect it. Some functions will work, but I can’t get it to read throttle %.
First of all, most responsive and helpful forum I have ever been on. Wow. Thank you.
I will be out in the shop in about 20 min and I will send all of that info over and try to be as thorough as possible. Thank you all so much for being so attentive.
1. This car has definitely been worked on…..I am assuming a lot. I inherited it from a shop that didnt want to deal with it anymore. I can see backprobe holes throughout the harness from where someone was stabbing away.
2. Manufacture date was 04/27/2011
3. Its using the QuiQ unit only as a dc to dc converter as it has been upgraded to a 72v bolt lithium that has its own standalone charger.
4 its the T4 controller but looks to be a reman unit.
5 its a rebuilt ride 4 fun pedal assembly. I have verified the internal switch is working correctly. I am not sure how to verify the pedal without it plugged in.
6. Its definitely not high current hitting the chassis. I have been trying to hunt down a 72v signal wire with no luck.
There is an added relay in here from the lithium conversion (i did not do the conversion) tied into the key switch that ties to the enable on the dc dc converter. I think it was to replace the charger interlock?
And as far as history, all I have really been told is that its had gremlins forever…as I can see by the swapped out parts everywhere.
I am an electrical and computer engineer by trade, but i can dabble in the mechanical as well. I started my shop doing golf cart, lsv, and small ev work a few months ago and developed a taste for the more complicated things the cart guys won’t touch.
I should have access to whatever tools I need for testing and verification (unless i need software beyond gentry- then I will need to get it loaded up). My hope is that I can help develop some tools to make these a little easier for everyone here. You tell me where to probe and what to test and I can report back with detail. I appreciate the support!
Flashes code 51 for a quarter second (which i am assuming is because the controller cap dissipated?)
Brake light has never gone away since I have had it. When I drop the parking brake, the 2 parking relays both click however. This pic is with the brake off. To answer the next question: if I keep the brake off and turn the key off I get a parking brake alert beep.
And the continuous beep is silenced by lifting HandbrakeON?
Verify(Y/N)?
The other thing that will trigger the Brake light will be low brake fluid level. Verify this is not faking you out by unplugging the fluid level sensor. It is up at the reservoir. Find a little two pin plug and disconnect.
Did the light go out?
Verify (Y/N)?
Fantastic!
It sounds like you have discovered the twin relays and they are working.
One of them triggers the beep, one more/less controls the light.
I am interested in the relay marked in this diagram as “Controller Relay”. It takes B- and sends it to P13 on the controller when handbrake is down.
