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Do this first
How to erase the DTC with SCS service connector

  1. Turn the ignition switch "OFF".
  2. Remove the front body cover (page 2-6).
  3. Remove the connector cover from the DLC [1] and short the DLC terminals using the special tool.
    TOOL:
    [2] SCS connector 070PZ-ZY30100 CONNECTION: Blue – Green/black

  4. Turn the ignition switch "ON".
  5. Disconnect the SCS connector [1] from the DLC [2].
    Connect the DLC short connector to the DLC again while the MIL stays ON about 5 seconds (reset receiving pattern).
  6. The stored DTC is erased if the MIL goes off and starts blinking (successful pattern).
  • The DLC must be jumped while the MIL lights. If not, the MIL will go off and stay on (unsuccessful pattern). In that case, turn the ignition switch to "OFF" and try again from step 3.
  • Note that the self-diagnostic memory cannot be erased if the ignition switch is turned “OFF” before the MIL starts blinking.
    CIRCUIT INSPECTION

    then do the


    TP SENSOR RESET and ECM reset

    Good luck





 

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Discussion Starter #24
grabbed my spare ecu from the shop down here that had it on loan, got talking to chuck about what the symptoms were on that bike. pretty much the exact same thing. so, will hopefully find out tonight when i get home.
 

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If your injector tests good, you could check continuity of wires going to injector, unless the harness has been stretched or stressed in some way with poor wire lead length it's usually not the case though. Next thing I'd check is the pickup coil. That will cause all the issues you were having. Check above the LH case first, just in case your connector came loose
 

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Discussion Starter #27
already pulled stator out and checked leads straight from pickup and the windings themself. all checked ok (cold of course). next step is to check the wire condition in the harness. i did order a spare stator/pickup, should be here wed. aside from that im totally stumped here's a brief rundown:

spark: none.
fuel pump is pressurising
injector isnt firing
afr went lean.
battery is good, even tested with larger one to make sure there wasnt a low battery voltage thing

so i bypassed the power commander, still same thing.

swapped ecu to my known good spare, nothing.

checked resistance on injector: 11.7 swapped injector: nothing

checked cam timing: perfect. pulled stator housing checked resistance on pickup and looked for broken wires: all good.

motor turns over. all connections seem ok. no engine light is coming on


however, saturday, it DID fire up briefly and sound fine for about 2 minutes, then die again.

almost feels like i have a dead wire in the harness somewhere. have no idea how, nothings been cut.

if i cant find it, ill gut the bike, build a fresh harness with a standalone cdi and carb it. maybe...
 

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Been following this thread pretty closely. Electrical problems are the worst. :(

Not to be a vulture, but let me know if you want to sell your throttle body. If you do go carb, she'll need a loving home.
 

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Discussion Starter #31
checked sidestand switch, kill (at bar), bank angle sensor (tip over switch), and clutch switch as well. keep in mind it wont turn over if the sidestand, clutch, or bar kill switch is inop.
 

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Check F1 Fuse

Seems like the coil is attached to pin 11 on the ECM via a "pink/blue" wire and the other end of the coil wire goes to the ING ON/OFF switch via a "BLK/WHT" wire so the same ING connection also goes to the F1 "10a fuse". I would check the connection to the ECM via pin 11 and the Fuse connection to the ING ON/OFF switch. Also check all areas around the fuse to make sure it has a good solid connection and maybe check and replace the fuse. The connection also goes to the DCL circuit.

Good Luck
 

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Discussion Starter #33
yeah but doesnt explain the injector not firing, since i checked all of that (fuses, conections int hat area. good idea though im going to do a full check on that turd later, have some 2-stroke projects taking precedence right now.
 

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yeah but doesnt explain the injector not firing, since i checked all of that (fuses, conections int hat area. good idea though im going to do a full check on that turd later, have some 2-stroke projects taking precedence right now.

F/I injector goes to the same F1 fuse, same wire also goes to the bank angle sensor and DCL. I have found on my fuse holder a loose/broken wire which cause intermittent problems
 

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Discussion Starter #36
F/I injector goes to the same F1 fuse, same wire also goes to the bank angle sensor and DCL. I have found on my fuse holder a loose/broken wire which cause intermittent problems
AGREED. but i checked all that already, and my bike never sits outside so corrosion is highly unlikely. however, keep in mind, it died at speed with no prior issues. im thinking i smoked a wire internally in the harness, maybe due to the increased load thru it due to cycle times, pretty sure i'll have to do a pin-to-pin resistance/continuity check on the main harness.

in the meantime: stoneage technology. still light-years faster than a grom. lol. 70 R5, built in 69. serial no #002000

70r5.jpg
 

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Discussion Starter #38
its all original, thanks. its going to stay as it is, just had to do some repairs, new tires, etc. it had the absolutely most slap worn out ft sprocket on it ive ever seen on a running bike.

few yrs ago (probably 8) i restored a 71 that was really a fun bike. that purple one (which is 99% done, new tires on it last night) and this one below (getting wheels built) need to get attention before I tie up time on the grom for an extended period of time.

rd-mono-motor_42_zpsus4gfrdx.jpg
 

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Discussion Starter #40
some i actually got a replacement main harness, finally got time to work on it and (it took forever) got the original out of the frame and am currently reinstalling the replacement.. hopefully i'll know something this weekend as i have plans tonight and friday.
 
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