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Discussion Starter · #1 ·
I have P1001 System Relay Coil Open/Low code come up every time when I connect Power Commander V (PCV).

If I remove PCV -- code does not show up. If I connect it -- it immediately happens (red dot, and diagnostics show P1001).

Bike runs just fine with PCV, I haven't noticed any issues. I hear fuel pump when I use Engine Stop Switch (and again, bike starts and runs just fine).

I checked resistance of wires -- everything looks fine. I even tried adding my "bypass" wires based on the wiring diagram, in case there is bad connection somewhere (PCV is connected between ECM and everything else, so it could theoretically affect connectivity). I swapped relays (they all seems to have he same type) -- doesn't make any difference.

Any ideas what could be going on? I contacted DynoJet, seems like they haven't seen anything like that in the past :/
 

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"Loose Nut" from Houston, Texas
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Is your Power Commander new or used? If new, then it appears to have a defect, have them replace it.
 

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Very simple and very complex at the same time. Watch how the processor takes in data:
1. Wire out of connector = Codes. There are no wires out of connector so no code set. Not it.
2. Connector not connected = Codes. There is no disconnect when all are hooked up. Not it.
3. Sensor/Wire:
a. Short = There is no [direct] short, no fuse blown, etc. Not it.
b. Open = This means a cut wire somewhere between the processor and the sensor. Not it.
c. Signal out of range = This is it and codes the bike. If you are not within an ohm's type of range in the design, you hacked into a wire that expects a square wave and you caused a saw blade type wave that is not readable.

"Runs just fine' means it is not going to alter fuel or ignition. Why? You are wired on the output side and captured that signal going out and remapped it with the PC. Let it code. Normal ping back and forth to set the code... oh well. No harm no foul... unless it's down the road when you check plugs.

EDIT:

"If I remove PCV -- code does not show up. " Correct.
Notice how zero problems with the bike's system. It self-diagnoses itself. There is nothing to check on FI bikes when no codes are showing. Relay wise I might be wrong on this; not being near that relay to find out.

I'm watching how the processor goes right back to a perfect balance of resistances when you do not tamper with a fixed formula design like a computer bike. It un-codes itself. To the guess on the relay... the processor basically has two moves. That's a magnetically fixed 'on,' or the current is lost/sig's range is out, and 'off' is the change or the flipflop in computer terms.

Relay wise, I'm wondering about P1001 System Relay Coil Open/Low. If I read this correctly, it is not open, but there is a 'low' and that means signal low or out of range. Again, I need a wire diagram to see what that relay is used for?

Another guess as I try to walk this out, I somehow tapped into a fuel loop with the PC? Coil is timing and fuel is timing. Is the relay in a harmonic vibration and low is a new resistance is the PC black box itself the resistor change?

Can we direct me to a factory shop manual pdf? Here is what I would do safety wise. I now have the PC off, so I am going to check timing with a strobe light and note the timing. I reinstall the PC and see there is no change in timing, I am good to go.

Short of installing an AFR and weld a bung in the pipe for the 02 sensor and ride both with and without PC, the fueling interplays with timing so I'd feel safe to ride it, sans looking at that relay wiring and where it goes to?

Only that relay wiring knows for sure.
 

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Discussion Starter · #4 ·
Is your Power Commander new or used? If new, then it appears to have a defect, have them replace it.
It's used. DynoJet solution is to offer me a discount on a replacement unit.

The puzzling part is that "system relay" wire goes straight through the connectors. It doesn't even go to PCV, wire goes straight connector to connector on PCV side.

Oh, and also there are two connectors on ECM ("gray" and "black"), PCV "hijacks" both. I tried connecting only one half of PCV (for example, leave original "black" as is and connect PCV only on the "gray" side). In both experiments ("gray" without PCV / "black" without PCV) the indication doesn't turn on.

My only remaining theory is that it is somehow possible to raise codes via CAN Bus and once PCV comes online it tells ECM something that it doesn't like. Actually... Display must be getting codes via CAN Bus, I wonder if PCV interferes somehow?..

I think, I'm going to monitor it and see if anything happens.
 

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Oh, and ... In both experiments ("gray" without PCV / "black" without PCV) the indication doesn't turn on.
Hook up the non-coding wire. Does bike sense or do you sense the PC has changed the performance without triggering the code? Yes.

Get it? No need to monitor because you did not limp the bike to some backup to save the engine from damage. It throws up a timing curve and you lose some HP. But now with light off, you are free to tune for torque and HP till the plugs foul too rich... No 02 on this bike, right? Or you're wasting your time short of coding the the 02 and disconnect it, ziptie the wire from burning. Ignore the code.

Here is what and only CAN does... there are a bunch of wires heading up to the dash in one fat wire harness, and in those wires are readouts of all sorts of codes ready to be sent; once it is breached. It separates signals so no speedo read bleeds onto the gas gauge and so on. CAN means two wires are twisted together only, and those are the hi/low CAN communication wires out of the ECM so each wire to the dash has no interference when data is sent to the dash... period.

CAN drops a wire, you see half or whatever codes are thrown at the dash. Drop the hi wire, I'm going to assume the other side of the dash and those codes will follow as did the other set of codes on the other side of the dash. Ask me how I know?

The node knows...

My only remaining theory is that it is somehow possible to raise codes via CAN Bus and once PCV comes online it tells ECM something that it doesn't like. Actually... Display must be getting codes via CAN Bus, I wonder if PCV interferes somehow?
Go look back at the troubleshooting tree theory as to how a code is sent 3 and only 3 ways. CAN just sends either one of the 3 of that sensor that is open/out of spec/connector, etc.

Watch how the processor catches the code:
Analog into the black box and digital out of the other side and the PC changes that wave length to the injector. PC is on the output side.
Digital now enters on the analog side is that sensor or relay that was breached 1 of 3 ways. ECM now reads a single digit of binary that always comes in as 0000 0000 0000. Analog should be making numbers like 0011 0101 1000 and so on. Think of it as zero going into the analog side of the processor = Codes.

ECM goes from on to off and thus, sends a blinking or sets a solid light at the dash. Because you now did not send in the digit on the wire-up on the PC, the ECM can again calc the numbers and sent it out to the coil, injector, etc.

Did that make sense how the bike codes with wire tampering on the wrong side being the input signal? And now if this is a learn ECM with a relay to shut it off after learn? Anyone have a shop manual to knows if the processor stays awake with key off?

EDIT:
Read your title again, so as I learn this ECM and a container load of P-codes, I'll assume Low is the low wire side of the dash... not sure, but low means CAN to me. And has nothing to do with CAN meaning, but the dash side, if you followed my abstract.
 
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