pitcelica's install : v3.57+MS3+MS3X
Posted: Thu Aug 26, 2010 3:36 pm
Hello everyone!
Here's my project :
The car :
1991 Toyota Celica GT-S with a 4th gen 3SGTE engine swap from a 1997-2002 Caldina GT-T
The engine :
4 cylinders, 2.0L, turbo, COP with built-in igniters, high-impedance 540cc/min injectors, 36-2 crank trigger wheel, a trigger arm on the intake camshaft, crank and cam sensors are both VR sensors, OEM (Toyota) CLT, MAP and IAT sensors, AEM UEGO gauge and wideband, 3-wire OEM PWM idle valve.
The brain :
v3.57 main board + MS3 + MS3X.
The history :
Previously, this engine was running nicely with a MS2 v3.0 using a EDIS ignition system (36-1 crank trigger wheel, Ford VR sensor, EDIS coilpack, EDIS module, custom spark plug wires). Last winter, I decided to convert it to stock wiring, stock ECU, stock sensors, stock everything (when I did the swap initially, I bought the engine without any ECU and a cut wiring harness, so I went MS2 at the first time. I sourced all the OEM missing parts right after the swap). This summer, the engine ran nicely on the stock ECU, but, I felt like I needed some more way to fine tune the engine for more power. While I was doing the conversion to the stock ECU, I tried to go full sequential and I added a bunch of board modifications and add-on boards to the MS2 and it resulted in a fried MS2 chip. I discovered that my DIY electronics skills are limited. I learned that I should let the pros do their job and pay for it. So, I bought a brand new complete MS3 unit from DIYautotune last week. In the mean time, I did an adapter harness to be able to switch from the stock ECU to the MS3 unit by only disconnecting 4 ECU plugs. I used a 31/24/22/28 receptacle, a female solder cup DB37 connector and a male solder cup DB37 connector.
The goal to achieve with the MS3+MS3X :
-full sequential fuel injection
-full sequential ignition timing (COP)
-fan control
-tacho output
-launch control/flatshift
-warning light (for shift light, overheat detection, overboost detection, or anything else that should be useful)
-closed-loop EGO control
-closed-loop idle control
-closed-loop boost control
-barometric compensation (using the on-board 3bar MAP sensor for it, I'll use the stock MAP sensor for the main load calculation)
I've attached an Excel file that shows my pinout choice for all the needed outputs and input on the MS3X.
Here's where I am :
I received the MS3 unit today. First thing I did was burning in the latest v0.26 firmware, burning in my .msq file (I created my .msq file offline by starting with the default.msq file). Everything went nicely using a Megastim and a known to be working USB-serial adaptor.
I removed the stock ECU and I plugged in my adapter harness. Just before plugging in my MS3, I've measured the electrical potential between the chassis ground and all the pins of both DB37 connectors while the ignition key is at ON. I was expecting to have only 12V on pin 28 on the MS3 connector, but I discovered that all the following pins have about 12V (between 10V-12V) of electrical potential between the chassis ground and the said pins :
MS3 connector :
pins # : 19-20-21-22-23-26-28-37
MS3X connector :
pins # : 10-13-16-19-24
Before plugging the MS3 unit, I would like to know if these voltages are OK. My main concern is pin #19, it is supposed to be my sensors grounds. All the grounds from my sensors are coming to that pin, so, why it have an electrical potential between sensors ground and chassis ground!! I seriously do not want to fry my MS3. I'm pretty sure that my main wiring harness is OK because this is the same harness that the stock ECU is using since April 2010. For the adapter harness, I've tested it for continuity and shorts and it's OK. I've even did the same voltage testing without the adapter harness and I've found the same values, so the adapter harness should be OK.
If my stock ECU was using this harness since 5 months, why MS3 couldn't handle it!
I'll update this thread as soon as I have some more questions or updates to share with all of you!
Thanks!
Sam
Here's my project :
The car :
1991 Toyota Celica GT-S with a 4th gen 3SGTE engine swap from a 1997-2002 Caldina GT-T
The engine :
4 cylinders, 2.0L, turbo, COP with built-in igniters, high-impedance 540cc/min injectors, 36-2 crank trigger wheel, a trigger arm on the intake camshaft, crank and cam sensors are both VR sensors, OEM (Toyota) CLT, MAP and IAT sensors, AEM UEGO gauge and wideband, 3-wire OEM PWM idle valve.
The brain :
v3.57 main board + MS3 + MS3X.
The history :
Previously, this engine was running nicely with a MS2 v3.0 using a EDIS ignition system (36-1 crank trigger wheel, Ford VR sensor, EDIS coilpack, EDIS module, custom spark plug wires). Last winter, I decided to convert it to stock wiring, stock ECU, stock sensors, stock everything (when I did the swap initially, I bought the engine without any ECU and a cut wiring harness, so I went MS2 at the first time. I sourced all the OEM missing parts right after the swap). This summer, the engine ran nicely on the stock ECU, but, I felt like I needed some more way to fine tune the engine for more power. While I was doing the conversion to the stock ECU, I tried to go full sequential and I added a bunch of board modifications and add-on boards to the MS2 and it resulted in a fried MS2 chip. I discovered that my DIY electronics skills are limited. I learned that I should let the pros do their job and pay for it. So, I bought a brand new complete MS3 unit from DIYautotune last week. In the mean time, I did an adapter harness to be able to switch from the stock ECU to the MS3 unit by only disconnecting 4 ECU plugs. I used a 31/24/22/28 receptacle, a female solder cup DB37 connector and a male solder cup DB37 connector.
The goal to achieve with the MS3+MS3X :
-full sequential fuel injection
-full sequential ignition timing (COP)
-fan control
-tacho output
-launch control/flatshift
-warning light (for shift light, overheat detection, overboost detection, or anything else that should be useful)
-closed-loop EGO control
-closed-loop idle control
-closed-loop boost control
-barometric compensation (using the on-board 3bar MAP sensor for it, I'll use the stock MAP sensor for the main load calculation)
I've attached an Excel file that shows my pinout choice for all the needed outputs and input on the MS3X.
Here's where I am :
I received the MS3 unit today. First thing I did was burning in the latest v0.26 firmware, burning in my .msq file (I created my .msq file offline by starting with the default.msq file). Everything went nicely using a Megastim and a known to be working USB-serial adaptor.
I removed the stock ECU and I plugged in my adapter harness. Just before plugging in my MS3, I've measured the electrical potential between the chassis ground and all the pins of both DB37 connectors while the ignition key is at ON. I was expecting to have only 12V on pin 28 on the MS3 connector, but I discovered that all the following pins have about 12V (between 10V-12V) of electrical potential between the chassis ground and the said pins :
MS3 connector :
pins # : 19-20-21-22-23-26-28-37
MS3X connector :
pins # : 10-13-16-19-24
Before plugging the MS3 unit, I would like to know if these voltages are OK. My main concern is pin #19, it is supposed to be my sensors grounds. All the grounds from my sensors are coming to that pin, so, why it have an electrical potential between sensors ground and chassis ground!! I seriously do not want to fry my MS3. I'm pretty sure that my main wiring harness is OK because this is the same harness that the stock ECU is using since April 2010. For the adapter harness, I've tested it for continuity and shorts and it's OK. I've even did the same voltage testing without the adapter harness and I've found the same values, so the adapter harness should be OK.
If my stock ECU was using this harness since 5 months, why MS3 couldn't handle it!
I'll update this thread as soon as I have some more questions or updates to share with all of you!
Thanks!
Sam