1995 OBD1 Diag tool
08-11-2006, 04:57 PM
#121
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Originally Posted by cowtown
I used expresspcb.com this time just because they give you free layout software and are here in CA. I don't have enough experience with this PCB stuff to figure out CAD tools, etc.
08-11-2006, 10:13 PM
#122
"Quality seems very good. We can definitely condense it down to about 1/2 this size if we do another run."
Why are the component labels on the circuit track side? The typical/standard is to
place the labels on the opposite side of the circuit tracks and from where the
components are actually inserted during the assembly process. This aids in the
assembly process, final test, and during troubleshooting if necessary.
Hopefully, the components aren't to be inserted from the circuit track side which
would affect the soldering process which might be assumed because of the
labels.
Why are the component labels on the circuit track side? The typical/standard is to
place the labels on the opposite side of the circuit tracks and from where the
components are actually inserted during the assembly process. This aids in the
assembly process, final test, and during troubleshooting if necessary.
Hopefully, the components aren't to be inserted from the circuit track side which
would affect the soldering process which might be assumed because of the
labels.
Last edited by Lorenfb; 08-11-2006 at 10:42 PM.
08-11-2006, 11:24 PM
#123
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Loren,
(Edit- )
I recently assembled a Megasquirt EFI computer, which uses a similar setup of traces and markings and components on top (although with a 4-layer board).
In this 993 OBD PCB, traces, markings and components are on top. Solder is applied on the botom thru-holes, which are plated through. No problem. If that really bothers anyone, components could be mounted on the bottom.
Colin
(Edit- )
I recently assembled a Megasquirt EFI computer, which uses a similar setup of traces and markings and components on top (although with a 4-layer board).
In this 993 OBD PCB, traces, markings and components are on top. Solder is applied on the botom thru-holes, which are plated through. No problem. If that really bothers anyone, components could be mounted on the bottom.
Colin
Last edited by cowtown; 08-13-2006 at 04:30 PM.
08-12-2006, 02:40 AM
#125
Ray, Doug, Lawrence, Colin,
threads got a bit off course but so far I've used it now to clear ecu faults, kept an eye on head temperatures with my engine tray off at some speed, determined that the intake temperature by moving my air filter on my TPC'd car to the back of the engine bay made no difference to the intake temperature above 50mph ie tail up, diagnosed an air conditioning problem, checked the throttle angle position sensor was working smoothly through various throttle posiitons, checked that my abs light was still working and found all sorts of other ways to spend time tinkering. And all this because a few remotely connected enthusiasts decided to challenge the norm.
Its been fun as well, cheers, Mark.
threads got a bit off course but so far I've used it now to clear ecu faults, kept an eye on head temperatures with my engine tray off at some speed, determined that the intake temperature by moving my air filter on my TPC'd car to the back of the engine bay made no difference to the intake temperature above 50mph ie tail up, diagnosed an air conditioning problem, checked the throttle angle position sensor was working smoothly through various throttle posiitons, checked that my abs light was still working and found all sorts of other ways to spend time tinkering. And all this because a few remotely connected enthusiasts decided to challenge the norm.
Its been fun as well, cheers, Mark.
Last edited by E6MPB; 08-13-2006 at 11:17 AM.
08-12-2006, 11:07 PM
#126
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Originally Posted by E6MPB
Ray, Doug, Lawrence, Colin,
threads got a bit off course but so far I've used it now to clear ecu faults, kept an eye on head temperatures with my engine tray off at some speed, determined that the intake temperature by moving my air filter on my TPC'd car to the back of the engine bay made no difference to the intake temperature above 50mph ie tail up, diagnosed an air conditioning problem, checked the throttle angle position sensor was working smoothly through various throttle posiitons, checked that my abs light was still working and found all sorts of other ways to spend time tinkering. And all this because a few remotely connected enthusiasts decided to challenge the norm.
What more can I say. Mark.
threads got a bit off course but so far I've used it now to clear ecu faults, kept an eye on head temperatures with my engine tray off at some speed, determined that the intake temperature by moving my air filter on my TPC'd car to the back of the engine bay made no difference to the intake temperature above 50mph ie tail up, diagnosed an air conditioning problem, checked the throttle angle position sensor was working smoothly through various throttle posiitons, checked that my abs light was still working and found all sorts of other ways to spend time tinkering. And all this because a few remotely connected enthusiasts decided to challenge the norm.
What more can I say. Mark.
Ray
08-15-2006, 09:50 PM
#127
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Interface pcb assembled tested
Here are photos of cowtowns pcb assembled and working. I assembled it to plug directly into the back of my laptop. The program switches face me. The components are out of the way. But more than one way to skin a cat.
I checked out the signal levels and all controllers. Its good.
Ray
I checked out the signal levels and all controllers. Its good.
Ray
Last edited by raycm; 08-17-2006 at 08:19 PM.
08-16-2006, 06:50 AM
#129
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Absolutely top work, guys !! 
Would it be precipitate to suggest 'Its time for production' ?? Perhaps a group buy on the PCBs, leave individuals to source electronics ?? Unless someone wants to offer a component GB, or even sell a built and tested board / assembly ...
BTW, did I miss the component list, or is it just as listed on the schematic ?
Thanks again, guys .. cheers, Maurice
Would it be precipitate to suggest 'Its time for production' ?? Perhaps a group buy on the PCBs, leave individuals to source electronics ?? Unless someone wants to offer a component GB, or even sell a built and tested board / assembly ...
BTW, did I miss the component list, or is it just as listed on the schematic ?
Thanks again, guys .. cheers, Maurice
08-16-2006, 12:52 PM
#130
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Brilliant work, guys ...kudos! Not to mention a huge thanks for doing the brainwork + r & d!! As for Maurice's request, may I second that ... 
Edward
Edward
08-16-2006, 04:19 PM
#131
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I'm up for a GB for a complete plug-and-play unit, for those of us who are electronically challenged. I'm at the "if my dog chews through the lamp cord, and the juice runs out on the floor, will I get shocked if I sweep it up?" level...
08-16-2006, 07:23 PM
#132
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I'm probably going to have to go that route as well. I tried to build an interface from the original schematics, but never could get scantool to connect with the one I built.
08-16-2006, 07:41 PM
#133
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Ray's got a couple more things to put in and I've got a minor rev. of the board to make assembly easier, and then it's ready to go. Give us 1-2 more days. I don't know if this qualifies as a "group buy" or not, but if there are some sort of procedures to follow, let me know.
I'm willing to get boards made up using the same service as before, and send them out, as long as the money is collected first. They need to be ordered in multiples of 3 so we would need 3 or 6 or 9 etc. people who want the PCBs. They would cost $26 each (not per 3) including shipping to CONUS addresses. This is for the bare board only. Components, box, beer, solder sold separately. The $26 would be pure cost - no one's making any money.
If anyone wants to take on the project of shopping around for a cheaper PCB house just shoot me a PM and I can figure out how to transfer the artwork to you. I've burned up all my free time and my wife is starting to wonder who I am.
Colin
I'm willing to get boards made up using the same service as before, and send them out, as long as the money is collected first. They need to be ordered in multiples of 3 so we would need 3 or 6 or 9 etc. people who want the PCBs. They would cost $26 each (not per 3) including shipping to CONUS addresses. This is for the bare board only. Components, box, beer, solder sold separately. The $26 would be pure cost - no one's making any money.
If anyone wants to take on the project of shopping around for a cheaper PCB house just shoot me a PM and I can figure out how to transfer the artwork to you. I've burned up all my free time and my wife is starting to wonder who I am.
Colin
08-16-2006, 08:46 PM
#134
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Originally Posted by maurice97C2S
BTW, did I miss the component list, or is it just as listed on the schematic ?
Good idea. BOM:
C1 0.1uF 25 Volt (such as Vishay A104K15X7RF5TAA or K104Z15Y5VE5TL2)
(C2) 100uF (such as Vishay 515D107M025AA6A)
OR (not preferred)
C1 .22u
D1 1N4148 Diode
D2 1N4148 Diode
D3 1N4148 Diode
J1 DB9 FEMALE
Q1 2N3904 NPN Transistor
Q2 2N3904 NPN Transistor
Q3 2N3904 NPN Transistor
Q4 2N3906 PNP Transistor
R1 2.2K Resistor 1/4W
R2 2.2K Resistor 1/4W
R3 2.2K Resistor 1/4W
R4 1K Resistor 1/4W
R5 1K Resistor 1/4W
R6 33K Resistor 1/4W
R7 33K Resistor 1/4W
R8 33K Resistor 1/4W
R9 33K Resistor 1/4W
L1 LED
L2 LED
L3 LED
S1 SWITCH SPDT
S2 SWITCH SPDT
FUSE FUSE
OBD OBD CONNECTOR OF YOUR CHOICE
Last edited by cowtown; 08-18-2006 at 03:01 PM.
08-17-2006, 03:00 AM
#135
Motronic Parameters Meanings
Is there some information somewhere on what the various Motronic settings mean? I haven't managed to find anything, at least nothing complete.
I'm especially interested in what the meaning is of the various values returned from the Motronic, what the ranges of the variables are, and what the implications are if a value is out of range. For example, what are "NTC 1" and "NTC 2", and what is a good range for the Oxygen sensor value?
I tried the Adaptation feature on my 964 this evening. The pre-Adaptation values are on the left, and post Adaptation on the right, in the pic below. I know the Adaptation doesn't alter many (any?) of these, but was interested particularly to see that the idle speed was reduced. Do the values look "OK"?
I'm especially interested in what the meaning is of the various values returned from the Motronic, what the ranges of the variables are, and what the implications are if a value is out of range. For example, what are "NTC 1" and "NTC 2", and what is a good range for the Oxygen sensor value?
I tried the Adaptation feature on my 964 this evening. The pre-Adaptation values are on the left, and post Adaptation on the right, in the pic below. I know the Adaptation doesn't alter many (any?) of these, but was interested particularly to see that the idle speed was reduced. Do the values look "OK"?