Well Hell, more original parts need to go

Whole reason I got the gem was it’s cooler then a golf cart for a golf cart parade. Parade was today, bricked and fixed charger, have Chinese bms, charged balances ran test run to guesstimate range today. Charged put everything back together, old wet cell in back for radio and Christmas lights, pushed dash back down and decorated.

Go to start it and error -15… ■■■■ already 30 minutes behind, overcharged to 98 volts on a Chevy volt 4x6s setup. Figured it was over voltage, ran headlights a while trickled down and nothing. Measure white wire pin 1 and reading 32 volts… wtf

Messed with it awhile making sure in a rush I didn’t pull a wire out . Off on multiple times and now system doesn’t even power up with key. Bms reading shows 96.9v

Time to map out the board and start pulling stuff out.

M@

Crap that sucks: if your ever need to remove some voltage you can go to your local hardware and buy a 2000 w Water Heater element. Hook it to B+ and B- and drop it in a 5 gallon bucket of water and it will drain down the voltage nice and safe. I had to do this a few times to dial in my BMS so that it would charge to the correct voltage. I over charged a bunch of time till I got it dialed in

Thanks @grantwest for the tip!

Odd thing is error is -15 which I assumed at the time was over voltage, but is actually under voltage. Unless my bdi has a light burnt out I have a different issue.

Measuring 97 volts on battery and bms.
Measuring 97 volts on outside of fuse
Measuring 97 volts on other side of fuse at contractor.
Somehow measuring 37 volts pin 1 in motor controller at times, seems to fluctuate up to 97.

Also noticed voltage on the frame again.

Plan is to cut open the wire sheath/guard and check for frayed or pulled lines.

Print out 12v system wiring diagram and pull it all out of PCB and move them all to a new fuseblock I have being fed via the the DCI on the charger and pull all ground off frame.

Then see what is left on the PCB and figure out how to work around it and pull it out completely. Have had weird voltage jumps between the fuses on it on and off so time for it to go.

Less unknowns and more mobility to swapping controller and motor in the future.

Thanks!

M@

If you have a 2002 with a T2 controller and your at 97 volts then YES your car is not gonna start. It needs to be st 96 volts or below to start.,

This is if you have David’s “voltage spoof” installed at pin #1

If you don’t then do not pass go or collect $200

T1 Controller odd thing is before I put dash back on and charged I was driving it so either short somewhere or over charged it seems.

Thanks!

M@

I have installed 2 high-voltage (above 97 volt) lithium kits in both early and late model Gems.
What I have found is T-4 controlled gems have no problems running above 98 volts this of corse is with the addition of David’s voltage spoof installed on pin #1.

When I installed a high voltage kit on a T-2 powerd gem we found out the car will not start above 96 volts. The fix was to Never charge above 3.9-4.0 volts per cell on a 24cell system.
This is not a problem if you have one of Daves
BMS-24 balancers installed running Dave’s (charge controllers ) This aftermarket add on that plugs into the BMS 24 stops the Delta Q from charging right at 96 volts. What it does is the BMS removes the ground (via the white wire) from the charger and stops all charging at what ever voltage the user selects. So it allowes the user to sort of make what ever charge profile/finish voltage you want.

Another way of getting around this over charge issue and having to deal with a BMS 24 is to buy one of Daves chargery off board chargers. This secondary charger can be adjusted to pretty much to have any finish voltage you select. This allows you to compley work around the stock delta Q. OR you can use both together at the same time to “Quick charge” at as high as 25 amps. I personally have done it. Charges your pack at 1/2 the time it normally takes when you have the delta Q and the off board charger going at the same time.( disclaimer) you need 2 dedicated circuits to run 2 charges at the same time.

So long story longer.
T-1 & T-2 cars need daves spoof & CANT ever go above 96 volts. (This if for now some one may discover a fix)

T-3 cars (JUNK) I don’t recommend modifying T-3 controlled cars. People here have reported noting but issues.

T-4 cars with Daves voltage spoof can run above 99 volts.

T-5 cars (No info on these cars so far)

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This is the final wiring after eliminating the original pcb.
Timer is a “delay off” module. Maintaining power through intermittent glitches and after “key off” for xx seconds.
The rest should be straight forward.

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This is for the sure power conversion, but should show the way to converting to DCI charger.

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Timer function:

Momentary or maintained input, to “trigger”, turns enable output to dc-dc on, for xx seconds after trigger removed.

Relay is powered from 12v key and sends 72v to controller. P2 I believe.
P1 may be cont 72v. Don’t remember for sure.

Thanks @Inwo

PIN 1 is continuous and 2 is at key on, actually was checking that yesterday.

I’ll read through and let you guys know how it goes.

Thanks again!

M@

Pin one is where voltage is sensed.

Started snapping pics of the PCB and cutting the wire sheaths.

Plastic wire clips into the PCB are so old all the snap/clicks to hold them on cracked right off when lifting them up. That’s another 3-4 issues I’ll prevent in the future :smiley:

M@

How did you connect your radio to your extra battery…direct? Did you use the ignition key for acc power?

Have one of the old deep cycles in the back wired into a 30amp fuse and a sonoff dc Switch, then into a fuse block where stereo is wired at the time

Plan to move the 12v feed to the quiq DCI always on 12v for now until I get the 5ch sonoff dc Switch and then split them up between switched and always on.

M@

Found DCI OEM doc had pinout for the DT, thinking I can pull off everything not just 12v

Thanks!

M@

Finally got around to putting some time in again. New android auto head unit, running bms software. First leg of 12v dc coming from Charger dci to sonoff pro dc smart switch. Currently have wired the following:
1 - Radio Remote
2 - Backup Camera and rear view display
3 - Ground lights

Need to program keychain remote for the wife. Started setting up Alexa routines for voice control. Hopefully can move the key switch to slot 4 in the coming weeks.

More to come!

M@

And forgot to mention I added @Inwo voltage spoof. Now to find a smart switch that can handle 100 volts so I can switch spoof on when charged up all the way and back off when battery is getting low.

M@