Voltage Reg Issues
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If your question is about troubleshooting, configuration, or tuning, you MUST include your processor type (MS-I or MS-II) and code version in your post. If your question is about PCB assembly or modifications, you must also include the main board version number (1.01, 2.2 or 3.0).
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The full forum rules are here: Forum Rules, be sure to read them all regularly.
Read the manual to see if your question is answered there before posting. Many users will not reply if the answer is already available in the manual.
If your question is about troubleshooting, configuration, or tuning, you MUST include your processor type (MS-I or MS-II) and code version in your post. If your question is about PCB assembly or modifications, you must also include the main board version number (1.01, 2.2 or 3.0).
If you have questions about MS1/Extra or MS2/Extra code configuration or tuning, please post them at www.msextra.com Such questions posted here will be moved to: a temporary MSextra sub-forum, where they will be removed after 7 days
The full forum rules are here: Forum Rules, be sure to read them all regularly.
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SilentNight1647
- MegaSquirt Newbie
- Posts: 3
- Joined: Fri Apr 17, 2009 7:45 am
Voltage Reg Issues
I built my MS-II a few years back but tnever got it to work right after I finished assembling it it wouldn't connect to save my life. I know for a fact that C11 is not installed but near as I can tell that should not affect the serial communication. I checked the voltages on the CPU soket and they are a little low at 4.25 on all 1, 20, and 31. What should be my next step I would really like to figure out what is going on so I can run this in my car and any help would be greatly appreciated.
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msiddalingaiah
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Re: Voltage Reg Issues
Remove the CPU, check the voltage going in to the regulator.
Madhu
1990 Suzuki DR350S EFI Conversion
Returnless, adjustable electronic Fuel Pump Controller requires less power
1990 Suzuki DR350S EFI Conversion
Returnless, adjustable electronic Fuel Pump Controller requires less power
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SilentNight1647
- MegaSquirt Newbie
- Posts: 3
- Joined: Fri Apr 17, 2009 7:45 am
Re: Voltage Reg Issues
It checks the same on the socket as it does on the reg itself. I think I may have something grounded out on the stim it has a constant IG light.
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Matt Cramer
- Super Squirter
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Re: Voltage Reg Issues
What main board is this? It sounds like there's a partial short somewhere - or an inadequate power supply feeding your Stim.
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SilentNight1647
- MegaSquirt Newbie
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- Joined: Fri Apr 17, 2009 7:45 am
Re: Voltage Reg Issues
It's a V3 board. I can't figure out for the life of me what is causing this short I assume it is something in the ignition circuit but everything appears OK. I shouldn't have let it sit on my shelf so long I can't remember what I did and didn't do. Any pointers on potential points of failure? The stim is powered by a 12v wall adapter at 200mA.
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msiddalingaiah
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Re: Voltage Reg Issues
Disconnect MS from the stim, does the stim have good voltage at all points?
Disconnect as much as possible from MS and check all voltages.
Disconnect as much as possible from MS and check all voltages.
Madhu
1990 Suzuki DR350S EFI Conversion
Returnless, adjustable electronic Fuel Pump Controller requires less power
1990 Suzuki DR350S EFI Conversion
Returnless, adjustable electronic Fuel Pump Controller requires less power
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Matt Cramer
- Super Squirter
- Posts: 2951
- Joined: Sat Jul 03, 2004 11:35 am
Re: Voltage Reg Issues
To check for a short in the Megasquirt PCB, power up the Megasquirt on a Stimulator or on the car and check the following points for voltage with a multimeter.
You should find the same voltage as the battery voltage on the following points: S12, S12C, the center legs of Q9 and Q12, the left (non-banded) end of D3, the left leg of U5, and the left (banded) end of D9.
You should have 5 volts at the following points: S5, the two +5V holes in the proto area, the right (non-banded) end of D9, the right leg of U5, the left (banded) end of D19, and pins 1, 20, and 31 of the CPU.
Let me know where you find the correct voltages, and where you find the wrong ones.
You should find the same voltage as the battery voltage on the following points: S12, S12C, the center legs of Q9 and Q12, the left (non-banded) end of D3, the left leg of U5, and the left (banded) end of D9.
You should have 5 volts at the following points: S5, the two +5V holes in the proto area, the right (non-banded) end of D9, the right leg of U5, the left (banded) end of D19, and pins 1, 20, and 31 of the CPU.
Let me know where you find the correct voltages, and where you find the wrong ones.