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Thread: generator l term ?

  1. #1
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    generator l term ?

    what would cause the gen l term status bit to turn off at uncommon times under wot.. its never exactly the same rpm been chasing my tail on elec problems... and some logs show ignition voltage go to 9.9 volt under wot at times.. it never shows the true voltage when I check with volt meter 12.2 is highest ive seen usually in 11s but battery shows in 13s running


    2000 Camaro operating system
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    67 camaro 6.0lq4 turbo build in process
    89 mustang coupe ls1 80mmturbo, holley dominator efi on e85
    02 lexus is300 lq4, cam,headers,fast 92 intake
    and no there isnt anything in my yard unmodified

  2. #2
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    You need schematics and to start doing volt drop test with system loads. Ignition switches were bad to burn out on the older ones along with battery cables themselves. I can tell you that if the ecm drops to or sees below 10 to 10.5volts it will usually shut down on most of the older OS's... Surprised it hasn't for you yet. Verify with a volt meter that your only getting those voltages right at the ecm then back track from there using a decent schematic for your vehicle.
    2010 Vette Stock Bottom LS3 - LS2 APS Twin Turbo Kit, Trick Flow Heads and Custom Cam - 12psi - 714rwhp and 820rwtq / 100hp Nitrous Shot starting at 3000 rpms - 948rwhp and 1044rwtq still on 93
    2011 Vette Cam Only Internal Mod in stock LS3 -- YSI @ 18psi - 811rwhp on 93 / 926rwhp on E60 & 1008rwhp with a 50 shot of nitrous all through a 6L80

    ~Greg Huggins~
    Remote Tuning Available at gh[email protected]
    Mobile Tuning Available for North Georgia and WNC

  3. #3
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    its a swap so its an easy trace.. thanks..
    67 camaro 6.0lq4 turbo build in process
    89 mustang coupe ls1 80mmturbo, holley dominator efi on e85
    02 lexus is300 lq4, cam,headers,fast 92 intake
    and no there isnt anything in my yard unmodified

  4. #4
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    Brush skip? If it goes out at high RPM only, this is likely it.

  5. #5
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    Alternator is cheap enough to try for elimination purposes...
    2010 Vette Stock Bottom LS3 - LS2 APS Twin Turbo Kit, Trick Flow Heads and Custom Cam - 12psi - 714rwhp and 820rwtq / 100hp Nitrous Shot starting at 3000 rpms - 948rwhp and 1044rwtq still on 93
    2011 Vette Cam Only Internal Mod in stock LS3 -- YSI @ 18psi - 811rwhp on 93 / 926rwhp on E60 & 1008rwhp with a 50 shot of nitrous all through a 6L80

    ~Greg Huggins~
    Remote Tuning Available at gh[email protected]
    Mobile Tuning Available for North Georgia and WNC

  6. #6
    Usually an L terminal fault code indicates a generator failure or related problem. You're generator should be internally regulated (no PCM field control). The L terminal is an indicator to the PCM that the generator is not producing output. It is also the initial voltage potential to "start" the generator.

  7. #7
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    Quote Originally Posted by CRTD View Post
    Usually an L terminal fault code indicates a generator failure or related problem. You're generator should be internally regulated (no PCM field control). The L terminal is an indicator to the PCM that the generator is not producing output. It is also the initial voltage potential to "start" the generator.
    Usually, but he also shouldn't be having the different voltage readings at different locations which is why I highly recommend checking volt drops. Not uncommon to have a bad ground or loose connection after a drivetrain swap due to being bolted down over paint or poor tension on a terminal. A loose connection on the S circuit to the alternator can cause the same code... If you can back probe the signal circuit to the alternator and have battery voltage there then you should be OK to replace the alternator and fix the majority of your problem.
    2010 Vette Stock Bottom LS3 - LS2 APS Twin Turbo Kit, Trick Flow Heads and Custom Cam - 12psi - 714rwhp and 820rwtq / 100hp Nitrous Shot starting at 3000 rpms - 948rwhp and 1044rwtq still on 93
    2011 Vette Cam Only Internal Mod in stock LS3 -- YSI @ 18psi - 811rwhp on 93 / 926rwhp on E60 & 1008rwhp with a 50 shot of nitrous all through a 6L80

    ~Greg Huggins~
    Remote Tuning Available at gh[email protected]
    Mobile Tuning Available for North Georgia and WNC