Parallel Install Schematic
#1
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Here is what I've been e-mailing out... since so many people failed to following simple instructions (aka pm me to request) and instead chose to post requests all over the damn forum I'm posting it here. Please let me know if you don't understand something or if I fucked up (I didn't because it's working in my car).
Here is my schematic... I have a '97 so the wire colors will be different. If you do an internal ECU mod (like kingofl33t) you will need to use the diagrams from http://www.madracki.com/miata/wiring.html to determine the correct pins. Once you find the right pins you will want to solder directly to the pins for things like TPS, CLT, CAS1, CAS2, etc. For the fuel injectors and coils you will need to CUT the pins and spread them apart. The engine side will then get soldered to the center position on a switch (always connected part of a dual pole switch). The ecu side will get soldered to one of the outside rows of pins, and a wire will get soldered to the other side of the switch. If you follow my schematic you will have 3 switches. If you need additional help let me know, I'll be glad to do what I can for ya. Also, if you don't have powerpoint let me know and I'll save the file as a jpeg and re-send.
I used three of these
http://www.radioshack.com/product/in...entPage=family
Incase that link doesn't work it's radioshack P/N: 275-614. I can get you some pics, but they are going to suck. I don't own a digital camera except the one on my work phone.
Here is my schematic... I have a '97 so the wire colors will be different. If you do an internal ECU mod (like kingofl33t) you will need to use the diagrams from http://www.madracki.com/miata/wiring.html to determine the correct pins. Once you find the right pins you will want to solder directly to the pins for things like TPS, CLT, CAS1, CAS2, etc. For the fuel injectors and coils you will need to CUT the pins and spread them apart. The engine side will then get soldered to the center position on a switch (always connected part of a dual pole switch). The ecu side will get soldered to one of the outside rows of pins, and a wire will get soldered to the other side of the switch. If you follow my schematic you will have 3 switches. If you need additional help let me know, I'll be glad to do what I can for ya. Also, if you don't have powerpoint let me know and I'll save the file as a jpeg and re-send.
I used three of these
http://www.radioshack.com/product/in...entPage=family
Incase that link doesn't work it's radioshack P/N: 275-614. I can get you some pics, but they are going to suck. I don't own a digital camera except the one on my work phone.
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Looks similar to what I've been making for 90 cars.
http://i100.photobucket.com/albums/m...0Install/1.jpg
http://i100.photobucket.com/albums/m...0Install/1.jpg
#7
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that was the idea... I had all this made up for my own use but wasn't planning to share it. I felt, at the time, that Adam was providing a good service to the community and I didn't want to step on his toes. But, not responding to people for over a month on his progress is something I can't tolerate.
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Additional Info for parallel installs on 1.8L engines using the stock CLT:
You must remove bias resistors R4 & R7 (do not jumper, just leave open) to avoid affecting your stock ecu! This is important because your ecu will think the engine is colder than it really is, preventing your fans from comming on. I'll report back in the next few days with the stock ecu bias resistance value for '96/'97 cars once I get a chance to measure it. This value will be needed for the MS to know how to read the input voltage it sees (entered into megatune, no a hardware resistor).
You must remove bias resistors R4 & R7 (do not jumper, just leave open) to avoid affecting your stock ecu! This is important because your ecu will think the engine is colder than it really is, preventing your fans from comming on. I'll report back in the next few days with the stock ecu bias resistance value for '96/'97 cars once I get a chance to measure it. This value will be needed for the MS to know how to read the input voltage it sees (entered into megatune, no a hardware resistor).
#14
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Additional Info for parallel installs on 1.8L engines using the stock CLT:
You must remove bias resistors R4 & R7 (do not jumper, just leave open) to avoid affecting your stock ecu! This is important because your ecu will think the engine is colder than it really is, preventing your fans from comming on. I'll report back in the next few days with the stock ecu bias resistance value for '96/'97 cars once I get a chance to measure it. This value will be needed for the MS to know how to read the input voltage it sees (entered into megatune, no a hardware resistor).
You must remove bias resistors R4 & R7 (do not jumper, just leave open) to avoid affecting your stock ecu! This is important because your ecu will think the engine is colder than it really is, preventing your fans from comming on. I'll report back in the next few days with the stock ecu bias resistance value for '96/'97 cars once I get a chance to measure it. This value will be needed for the MS to know how to read the input voltage it sees (entered into megatune, no a hardware resistor).
#15
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as soon as I get my DC inspection I'm gonna start screwing around with setting up the hydra in parallel and seeing how it reacts to tapped sensors.
i'm pretty sure nobody runs one that way because you really dont need to. I just am doing it to do it. for EGR, better alternator control, better idle control, obdii "compatibility" and **** like that.
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nope... but it was enough that my stock computer didn't see 210* (fan on temp) until my gauge said 256*. I removed the bias resistors in the MS today and calculated the stock ecu bias. For future reference '97 miatas have a stock bias of 1.2Kohm, I suspect that '96 will be the same but I can't promise it.
To determine you stock bias resistor you will need to:
1) unplug the 8 pin harness above the fuel rail
2) measure the resistance between the blue with white strip and the black with blue strip wires which are directly across from each other on the female connector (this is the sensor resistance)
3) Reconnect connectors
4) Key on the car, but don't start it... check the voltage at your wire tap for the MS (MS disconnected).
Your bias resistor will equal:
R=R1 * [(5-V)/V)]
where R1 = measured sensor resistance from above
and V=your measured voltage at the wire tap
I calculated 1205 ohms, or 1.2k-ohms.
This value is then input to easytherm in the bias resistor box. After doing this my cooling fan is working again and megatune is reading accurately.
To determine you stock bias resistor you will need to:
1) unplug the 8 pin harness above the fuel rail
2) measure the resistance between the blue with white strip and the black with blue strip wires which are directly across from each other on the female connector (this is the sensor resistance)
3) Reconnect connectors
4) Key on the car, but don't start it... check the voltage at your wire tap for the MS (MS disconnected).
Your bias resistor will equal:
R=R1 * [(5-V)/V)]
where R1 = measured sensor resistance from above
and V=your measured voltage at the wire tap
I calculated 1205 ohms, or 1.2k-ohms.
This value is then input to easytherm in the bias resistor box. After doing this my cooling fan is working again and megatune is reading accurately.
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