# 2002 Gem Charge Level **URL:** \ **Category:** Battery & Chargers\ **Created:** [June 29, 2018, 2:53pm UTC](https://community.electricforum.com/t/2002-gem-charge-level/13992 "2018-06-29T14:53:02Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![MRSLR](https://avatars.discourse-cdn.com/v4/letter/m/a9a28c/32.png) [@MRSLR](https://community.electricforum.com/u/MRSLR)\ **Post date:** [June 29, 2018, 2:53pm UTC](https://community.electricforum.com/t/2002-gem-charge-level/13992/1 "2018-06-29T14:53:02Z")
Hey I just installed new Trojan batteries in my 2002 Gem 4 seater. Everything is running well except the charging level indicator will not change from “90”. I’ve turned off power under the back seat and reset it but still no change in charge level. Any suggestions? ---
**Author:** ![dougl](https://avatars.discourse-cdn.com/v4/letter/d/b19c9b/32.png) [@dougl](https://community.electricforum.com/u/dougl)\ **Post date:** [July 1, 2018, 1:17am UTC](https://community.electricforum.com/t/2002-gem-charge-level/13992/2 "2018-07-01T01:17:51Z")
search the forum for resetting the display or something like that. IIRC there is a little dance which needs to be done to reset that and another dance to adjust the levels higher and lower( turn signal switch movements ). The GEM forum - [https://community.electricforum.com/c/gem-forum](https://community.electricforum.com/c/gem-forum) ---
**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\ **Post date:** [July 1, 2018, 3:48am UTC](https://community.electricforum.com/t/2002-gem-charge-level/13992/3 "2018-07-01T03:48:58Z")
> [@dougl](#): > > search the forum for resetting the display or something like that. IIRC there is a little dance which needs to be done to reset that and another dance to adjust the levels higher and lower( turn signal switch movements ). > > The GEM forum - [GEM Forum - Electric Forum](https://community.electricforum.com/c/gem-forum) 2002 is different, the reason I didn’t hazard a guess. I’ll invite Rodney. I believe soc is sent from controller to display. And that there are settings that can change it. Reseat 8 or 12p connector and 23p connector. Worth a shot. ---
**Author:** ![Mr.Vern](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/mr.vern/32/2658_2.png) [@Mr.Vern](https://community.electricforum.com/u/Mr.Vern)\ **Post date:** [July 2, 2018, 5:39am UTC](https://community.electricforum.com/t/2002-gem-charge-level/13992/4 "2018-07-02T05:39:13Z")
If you have a programmer, fields 14 and 15 work together to make the SOC work properly. I have been playing with it but have not mastered it yet. Here is what the manual says(the table doesn’t format well in the forum but you can sort it out if you stare at it a minute): FUNCTION 14 INTERNAL RESISTANCE COMPENSATION ( Push 14 ) This function is used when the Battery Discharge Indicator is present. Adjustment of this function will improve the accuracy of the BDI. In order to determine this setting, the voltage drop of the battery under load must first be calculated by the following method: 1. Record open circuit voltage (Vo) by measuring the voltage at the control positive and negative power terminals. 2. Load the traction motor to 100 amps in 1A and record the voltage (VL) at the control positive and negative power terminals. 3. Calculate voltage drop (VDrop) as follows: VDrop = VO - VL 4. Use the table below to determine the appropriate setting using the calculated VDrop as a reference. INTERNAL RESISTANCE COMPENSATION TABLE Setting VDrop Setting VDrop 2 11.44 17 1.34 3 7.60 18 1.27 4 5.72 19 1.20 5 4.57 20 1.14 6 3.81 21 1.09 7 3.27 22 1.04 8 2.86 23 0.99 9 2.54 24 0.95 10 2.28 25 0.91 11 2.08 26 0.88 12 1.90 27 0.85 13 1.76 28 0.82 14 1.63 29 0.79 15 1.52 30 0.76 16 1.43 31 0.74 FUNCTION 15 BATTERY VOLTS (Push l5) In order for the battery discharge indication feature of this control to operate properly, this function must be set to a value between 70 and 80. ---
**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\ **Post date:** [July 2, 2018, 5:55am UTC](https://community.electricforum.com/t/2002-gem-charge-level/13992/5 "2018-07-02T05:55:27Z")
This is a case where the sentry monitor function is helpful. I can supply instructions or a kit for any one with the sw. All my cars have a programming port that stays with the car. Great for trouble shooting. Shows all the input switch positions. Temperature, amps, B+ volts, bus voltage. Graphs armature versus field or any other functions selected.