Lexus GS450H VCU Support Thread
- Jack Bauer
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Re: Lexus GS450H VCU Support Thread
2nd layer is vcc and third is gnd. Is this v2 or v1? I'm going to be testing some 65hvd230 can transcievers soon which they have as a basic part so that would bring things back in line.
I'm going to need a hacksaw
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Re: Lexus GS450H VCU Support Thread
I've written it in already in draft, but need the values for it, I've not had a chance to sort this yet.
It's based on the first Google result: https://www.google.com/search?q=arduino ... t+equation
Code: Select all
#define TEMP_MG1 0
#define TEMP_MG2 1
#define TEMP_TRANS 2
#define TEMP_OIL 3
float ntc_temp[8] = {0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f}; //temperature output in c
int ntc_raw[8] = {0, 0, 0, 0, 0, 0, 0, 0}; //0 to 1023 input
float ntc_ohms[8] = {0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f}; // R1* (1023.0 / (float)ntc_raw - 1.0};
float ntc_bias[8] = {249000, 249000, 18000, 680000, 100000, 10000, 15000, 100000}; //bias resistor in ohms
float log_ntc_ohms[8] = {0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f}; //working variable
float ntc_a[8] = {1.484778004e-03, 1.484778004e-03, 1.484778004e-03, 1.484778004e-03, 1.484778004e-03, 1.484778004e-03, 1.484778004e-03, 1.484778004e-03}; //steinhart-hart function
float ntc_b[8] = {2.348962910e-04, 2.348962910e-04, 2.348962910e-04, 2.348962910e-04, 2.348962910e-04, 2.348962910e-04, 2.348962910e-04, 2.348962910e-04}; //steinhart-hart function
float ntc_c[8] = {1.006037158e-07, 1.006037158e-07, 1.006037158e-07, 1.006037158e-07, 1.006037158e-07, 1.006037158e-07, 1.006037158e-07, 1.006037158e-07}; //steinhart-hart function
void process_ntc(byte i)
{
//at this point, we have already read ntc_raw from the input
ntc_ohms[i] = ntc_bias[i] * (1023.0 / (float)ntc_raw[i] - 1.0);
log_ntc_ohms[i] = log(ntc_ohms[i]);
ntc_temp[i] = (1.0 / (ntc_a[i] + ntc_b[i] * log_ntc_ohms[i] + ntc_c[i] * log_ntc_ohms[i] * log_ntc_ohms[i] * log_ntc_ohms[i]));
ntc_temp[i] -= 273.15;
}
void run_cooling()
{
ntc_raw[TEMP_MG1] = analogRead(pin_temp_mg1);
ntc_raw[TEMP_MG2] = analogRead(pin_temp_mg2);
ntc_raw[TEMP_TRANS] = analogRead(pin_temp_trans);
ntc_raw[TEMP_OIL] = analogRead(pin_temp_oil);
for (int i = 0; i > 8; i++)
{
if (ntc_raw[i] > 0 && ntc_raw[i] < 1023) process_ntc[i];
else ntc_temp[i] = 0.0f;
}
}
65HVD230 should work fine. I didn't use them because of the 5v levels in the Lexus unit, apparently others haven't had an issue though.Jack Bauer wrote: ↑Mon Mar 02, 2020 1:55 pm 2nd layer is vcc and third is gnd. Is this v2 or v1? I'm going to be testing some 65hvd230 can transcievers soon which they have as a basic part so that would bring things back in line.
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Re: Lexus GS450H VCU Support Thread
Awesome, thanks very much.xp677 wrote: ↑Mon Mar 02, 2020 8:41 pmI've written it in already in draft, but need the values for it, I've not had a chance to sort this yet.
It's based on the first Google result: https://www.google.com/search?q=arduino ... t+equation
This is for 8 NTC thermistors, adapt to suit for 4 for this VCU, or whatever you want. Untested, does compile.Code: Select all
#define TEMP_MG1 0 #define TEMP_MG2 1 #define TEMP_TRANS 2 #define TEMP_OIL 3 float ntc_temp[8] = {0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f}; //temperature output in c int ntc_raw[8] = {0, 0, 0, 0, 0, 0, 0, 0}; //0 to 1023 input float ntc_ohms[8] = {0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f}; // R1* (1023.0 / (float)ntc_raw - 1.0}; float ntc_bias[8] = {249000, 249000, 18000, 680000, 100000, 10000, 15000, 100000}; //bias resistor in ohms float log_ntc_ohms[8] = {0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f}; //working variable float ntc_a[8] = {1.484778004e-03, 1.484778004e-03, 1.484778004e-03, 1.484778004e-03, 1.484778004e-03, 1.484778004e-03, 1.484778004e-03, 1.484778004e-03}; //steinhart-hart function float ntc_b[8] = {2.348962910e-04, 2.348962910e-04, 2.348962910e-04, 2.348962910e-04, 2.348962910e-04, 2.348962910e-04, 2.348962910e-04, 2.348962910e-04}; //steinhart-hart function float ntc_c[8] = {1.006037158e-07, 1.006037158e-07, 1.006037158e-07, 1.006037158e-07, 1.006037158e-07, 1.006037158e-07, 1.006037158e-07, 1.006037158e-07}; //steinhart-hart function void process_ntc(byte i) { //at this point, we have already read ntc_raw from the input ntc_ohms[i] = ntc_bias[i] * (1023.0 / (float)ntc_raw[i] - 1.0); log_ntc_ohms[i] = log(ntc_ohms[i]); ntc_temp[i] = (1.0 / (ntc_a[i] + ntc_b[i] * log_ntc_ohms[i] + ntc_c[i] * log_ntc_ohms[i] * log_ntc_ohms[i] * log_ntc_ohms[i])); ntc_temp[i] -= 273.15; } void run_cooling() { ntc_raw[TEMP_MG1] = analogRead(pin_temp_mg1); ntc_raw[TEMP_MG2] = analogRead(pin_temp_mg2); ntc_raw[TEMP_TRANS] = analogRead(pin_temp_trans); ntc_raw[TEMP_OIL] = analogRead(pin_temp_oil); for (int i = 0; i > 8; i++) { if (ntc_raw[i] > 0 && ntc_raw[i] < 1023) process_ntc[i]; else ntc_temp[i] = 0.0f; } }
Re: Lexus GS450H VCU Support Thread
I haven't tried to run the code, but i would guess
if (ntc_raw > 0 && ntc_raw < 1023) process_ntc;
should be:-
if (ntc_raw > 0 && ntc_raw < 1023) process_ntc(i);
as process_ntc is a function rather than an array.
if (ntc_raw > 0 && ntc_raw < 1023) process_ntc;
should be:-
if (ntc_raw > 0 && ntc_raw < 1023) process_ntc(i);
as process_ntc is a function rather than an array.
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Re: Lexus GS450H VCU Support Thread
Yes it should. I wrote that part by hand in the Reply window here, because my code handles it in a different way which wouldn't work standalone.
The code would need integration anyway, so things like that will work themselves out.
I look forward to seeing you guys getting it working!
The code would need integration anyway, so things like that will work themselves out.
I look forward to seeing you guys getting it working!
- Jack Bauer
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Re: Lexus GS450H VCU Support Thread
New batch of V2 controllers has arrived from JLCPCB. This batch have the SAM3 processor fitted:)
I'm going to need a hacksaw
Re: Lexus GS450H VCU Support Thread
Jack Bauer wrote: ↑Wed Mar 04, 2020 5:56 pm New batch of V2 controllers has arrived from JLCPCB. This batch have the SAM3 processor fitted:)
Looks like my wallet is about to get a little bit lighter.

How are you selling these new ones? Partially assembled or fully tested?
- mdrobnak
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Re: Lexus GS450H VCU Support Thread
Hello everyone. This is definitely exciting stuff. I am trying to find part numbers for the inverter that Damien is using.
It looks like it's either G9200-30061 or G9200-30040? Are those both suitable candidates for use with the controller? I just noticed in the picture above is G9200-30030.
It looks like these devices are going for about $750 on Ebay. Anyone have better suggestions than that? I'm actually looking to use this in a hybrid conversion project, but that'll be its own thread when the time comes.
-Matt
It looks like it's either G9200-30061 or G9200-30040? Are those both suitable candidates for use with the controller? I just noticed in the picture above is G9200-30030.
It looks like these devices are going for about $750 on Ebay. Anyone have better suggestions than that? I'm actually looking to use this in a hybrid conversion project, but that'll be its own thread when the time comes.

-Matt
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Re: Lexus GS450H VCU Support Thread
I'm running on a G9200-30051, this is the unit that the firmware was developed on.
That's a RHD unit. Apparently the LHD unit and the Camry unit are compatible.
That's a RHD unit. Apparently the LHD unit and the Camry unit are compatible.
- Jack Bauer
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- mdrobnak
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Re: Lexus GS450H VCU Support Thread
Thanks for the part number, xp677. The thread here: https://www.clublexus.com/forums/build- ... hange.html seems to seem like someone either got a bad inverter, or there's gonna be some LHD / RHD issues.
Or I wonder if it's irrelevant due to the different control unit.
Going by the numbering pattern it seems like G9200-30061 LHD vs 30051 RHD, 30040 LHD vs 30030 RHD and likely 30180 LHD vs 30170 RHD.
Hopefully we have some people doing LHD in this thread that can confirm what works for them. Also I thought the person using the Camry inverter had no reverse? Or was that fixed?
-Matt

Going by the numbering pattern it seems like G9200-30061 LHD vs 30051 RHD, 30040 LHD vs 30030 RHD and likely 30180 LHD vs 30170 RHD.
Hopefully we have some people doing LHD in this thread that can confirm what works for them. Also I thought the person using the Camry inverter had no reverse? Or was that fixed?
-Matt
- jnsaff
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Re: Lexus GS450H VCU Support Thread
Wrong thread for this but I’ve gotten a lot of parts from these Lithuanian breaker brokers. Currently GS450h inverters from 400EUR. https://dalys.lt/en/autoparts/lexus/gs- ... e=1&sort=1mdrobnak wrote: ↑Thu Mar 05, 2020 5:13 pm Hello everyone. This is definitely exciting stuff. I am trying to find part numbers for the inverter that Damien is using.
It looks like it's either G9200-30061 or G9200-30040? Are those both suitable candidates for use with the controller? I just noticed in the picture above is G9200-30030.
It looks like these devices are going for about $750 on Ebay. Anyone have better suggestions than that? I'm actually looking to use this in a hybrid conversion project, but that'll be its own thread when the time comes.
-Matt
Delivery to my hood is usually 20 eur but ymmv.
Re: Lexus GS450H VCU Support Thread
I got my inverter for ~$350 on eBay. Look for ones you can submit offers. I am not ready to test if my inverter + gearbox work though. Still waiting to save up for the VCU.
Re: Lexus GS450H VCU Support Thread
I purchased and built a v2 vcu for the GS450h inverter. Could someone please tell me whether I need to provide 12v constant power to the board when flashing firmware to it? Or do I just simply connect the board to my pc via the onboard usb jack? If someone could provide instructions for flashing firmware to a new vcu, I would appreciate it. Thanks!
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Re: Lexus GS450H VCU Support Thread
Looking at the schematic, the USB port provides +5v to the circuit, so you should be fine with that.
- mdrobnak
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Re: Lexus GS450H VCU Support Thread
Apologies if this is not the right thread to put this in. I didn't think this warranted its own thread.
It is unfortunately unclear to me - does https://www.ebay.com/itm/123766966717 have the connectors required to connect to the inverter? To my eye it does. But I'm not sure, and I don't want to spend $300 on shipping if I'll still have to deal with finding connectors later. This one: https://www.ebay.com/itm/2007-Lexus-GS4 ... 2639993788 is cheaper but no HV cables and frankly doesn't look as good LOL.
Thoughts?
Thanks,
-Matt
It is unfortunately unclear to me - does https://www.ebay.com/itm/123766966717 have the connectors required to connect to the inverter? To my eye it does. But I'm not sure, and I don't want to spend $300 on shipping if I'll still have to deal with finding connectors later. This one: https://www.ebay.com/itm/2007-Lexus-GS4 ... 2639993788 is cheaper but no HV cables and frankly doesn't look as good LOL.
Thoughts?
Thanks,
-Matt
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Re: Lexus GS450H VCU Support Thread
Yes, it looks like it does. I don't think there is a difference in connectors between the Camry and GS inverters in the US - if the connectors don't fit for any reason, you can likely adapt the connectors to fit.
As far as I'm aware, any 2006-2011 GS inverter will work with that transmission. My project uses a 2007 inverter and 2010 transmission.
Note that I only have experience with the RHD units (which we also believe are the same), so can't guarantee accuracy.
Also note that the oil cooler pipes and transmission wiring harness is missing from this unit. The connectors seem to have been sorted in another thread here. For the trans cooler lines, you can likely get them from a junk yard, or make your own with banjo fittings (they go where the red plastic caps are on the side).
As far as I'm aware, any 2006-2011 GS inverter will work with that transmission. My project uses a 2007 inverter and 2010 transmission.
Note that I only have experience with the RHD units (which we also believe are the same), so can't guarantee accuracy.
Also note that the oil cooler pipes and transmission wiring harness is missing from this unit. The connectors seem to have been sorted in another thread here. For the trans cooler lines, you can likely get them from a junk yard, or make your own with banjo fittings (they go where the red plastic caps are on the side).
Re: Lexus GS450H VCU Support Thread
The first one looks good. You want to get them as complete as you can. There are some that don't come with the oil pump and those go for even more than the gearbox itself. I usually put in an offer around $350 to see how the seller responds. 

Re: Lexus GS450H VCU Support Thread
If I am reading this thread and the wiki page correctly, it seems that the Camry inverters can be used to run the gs450h transmission. Is this assumption correct? Or incorrect?
All I need is a tree and a come along
Re: Lexus GS450H VCU Support Thread
Is there an stl file or cad model available for this cover?xp677 wrote: ↑Thu Feb 20, 2020 12:50 am It's glued/bonded in - I had to smash mine out. I think I used a screwdriver and then a craft knife to clean up the rest. Be careful not to cut yourself or scratch the aluminium, it's a mating face for my cover!
DC bus cover pictured in my last post is done. I just want to add o-ring grooves around the cable entries, and a million other tiny things that I'll notice.
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Now onto the converter input cover!
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Re: Lexus GS450H VCU Support Thread
Question everyone. Can we assume all GS450h motors are all timed the same from the factory (Toyota equivalent to syncofs)? Otherwise each inverter would have to be configured for the right timing for each transmission.
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Re: Lexus GS450H VCU Support Thread
Not yet, still being prototyped. I've gone through 3 versions now, next one printing tomorrow, should be the final version (fingers crossed)