S5 ECU/ wiring clarification
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Joined: Apr 2002
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From: Yellowknife, NT
S5 ECU/ wiring clarification
1990 Rx-7 Turbo
I need to know if someone can scan and email me the wiring diagram I need the wiring diagram that feeds plug 1 at the ecu the body portion of the ecu harness.
I need to know the route that pin's 1A, 1B, 1C take.
jreynish@shaw.ca
I need to know if someone can scan and email me the wiring diagram I need the wiring diagram that feeds plug 1 at the ecu the body portion of the ecu harness.
I need to know the route that pin's 1A, 1B, 1C take.
jreynish@shaw.ca
Thread Starter
Joined: Apr 2002
Posts: 3,764
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From: Yellowknife, NT
yeah I am aware of that, but it does not have the diagrams that I am looking for those are about two dozen pages of about 200. So if somebody could email it to me or simply tell me the routes that thoes wires take going through and from what devices that would be great. Thanks
Thread Starter
Joined: Apr 2002
Posts: 3,764
Likes: 6
From: Yellowknife, NT
yes it does not have 1a and 1c listed on it... it tell me their function but not their route to to get there and what else they may be associated with. I have a burned wire in the wiring harness and want to know the points to check to see wich part of the wiring harness I need to cut open and fix that singel wire.
Full Member
Joined: Jul 2002
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From: Ottawa Canada
On page B-2a (TurboIgnition), pin 1a goes from the computer L/R wire to a 7.5A fuse inside the passenger compartment, out to the main fuse panel through the 60A fuse to the battery. Pin 1c can be found on B-2b(TurboECUOne), it goes from the computer to the circuit opening relay. Hope that helps.
Joined: Mar 2001
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From: https://www2.mazda.com/en/100th/
Originally Posted by slorimer
On page B-2a (TurboIgnition), pin 1a goes from the computer L/R wire to a 7.5A fuse inside the passenger compartment, out to the main fuse panel through the 60A fuse to the battery. Pin 1c can be found on B-2b(TurboECUOne), it goes from the computer to the circuit opening relay. Hope that helps.
1c is the 12v switched power?
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HAILERS
Joined: May 2001
Posts: 20,563
Likes: 27
From: FORT WORTH, TEXAS,USA
1A is constant power from the battery like you said.
1C acutally is 12vdc from the Start circuit TO the ECU, when you HOLD the key to START. It lets the ECU know your in the Start mode and then uses that signal plus engine rpm plus water thermo sensor temperature to govern how much fuel the injectors inject. No afm involved in the Start cycle. If 1C is depinned then the ECU uses the afm for fuel delivery when you go to Start. A little too lean though if done that way.
If memory serves, I pulled the BTN fuse that supplies pwr to the pin 1A (except on a S4, diff pin etc) and the engine still starts and runs without it. That's from memory. Check it out for yourself for verification.
And about the routing. If you look at the diagram that shows those wires, you'll see, as an example, L/R (F). The (F) means the wire is in the Front harness. So it'll route from the ECU to the fuse box in the interior. The FSM shows where the Front harness is routed in the car. Same with the EM harness, Rear harness etc.
IF that wire was open b/t the fuse box and ECU, then just piggyback a new wire from point to point and string tie to the Front harness.
1C acutally is 12vdc from the Start circuit TO the ECU, when you HOLD the key to START. It lets the ECU know your in the Start mode and then uses that signal plus engine rpm plus water thermo sensor temperature to govern how much fuel the injectors inject. No afm involved in the Start cycle. If 1C is depinned then the ECU uses the afm for fuel delivery when you go to Start. A little too lean though if done that way.
If memory serves, I pulled the BTN fuse that supplies pwr to the pin 1A (except on a S4, diff pin etc) and the engine still starts and runs without it. That's from memory. Check it out for yourself for verification.
And about the routing. If you look at the diagram that shows those wires, you'll see, as an example, L/R (F). The (F) means the wire is in the Front harness. So it'll route from the ECU to the fuse box in the interior. The FSM shows where the Front harness is routed in the car. Same with the EM harness, Rear harness etc.
IF that wire was open b/t the fuse box and ECU, then just piggyback a new wire from point to point and string tie to the Front harness.
Thread Starter
Joined: Apr 2002
Posts: 3,764
Likes: 6
From: Yellowknife, NT
Hailers once again thank you... you seem to be helping me with all of my wiring delemas... thanks to everyone else as well. I actually have four burnt wires in the front harness. So it seems that I will be replacing some serious wires, I have my dash out and all that out so that I can properly repair this harness. Thanks again everyone.
Joined: Mar 2001
Posts: 31,833
Likes: 3,232
From: https://www2.mazda.com/en/100th/
Originally Posted by HAILERS
1A is constant power from the battery like you said.
1C acutally is 12vdc from the Start circuit TO the ECU, when you HOLD the key to START. It lets the ECU know your in the Start mode and then uses that signal plus engine rpm plus water thermo sensor temperature to govern how much fuel the injectors inject. No afm involved in the Start cycle. If 1C is depinned then the ECU uses the afm for fuel delivery when you go to Start. A little too lean though if done that way.
If memory serves, I pulled the BTN fuse that supplies pwr to the pin 1A (except on a S4, diff pin etc) and the engine still starts and runs without it. That's from memory. Check it out for yourself for verification.
And about the routing. If you look at the diagram that shows those wires, you'll see, as an example, L/R (F). The (F) means the wire is in the Front harness. So it'll route from the ECU to the fuse box in the interior. The FSM shows where the Front harness is routed in the car. Same with the EM harness, Rear harness etc.
IF that wire was open b/t the fuse box and ECU, then just piggyback a new wire from point to point and string tie to the Front harness.
1C acutally is 12vdc from the Start circuit TO the ECU, when you HOLD the key to START. It lets the ECU know your in the Start mode and then uses that signal plus engine rpm plus water thermo sensor temperature to govern how much fuel the injectors inject. No afm involved in the Start cycle. If 1C is depinned then the ECU uses the afm for fuel delivery when you go to Start. A little too lean though if done that way.
If memory serves, I pulled the BTN fuse that supplies pwr to the pin 1A (except on a S4, diff pin etc) and the engine still starts and runs without it. That's from memory. Check it out for yourself for verification.
And about the routing. If you look at the diagram that shows those wires, you'll see, as an example, L/R (F). The (F) means the wire is in the Front harness. So it'll route from the ECU to the fuse box in the interior. The FSM shows where the Front harness is routed in the car. Same with the EM harness, Rear harness etc.
IF that wire was open b/t the fuse box and ECU, then just piggyback a new wire from point to point and string tie to the Front harness.
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