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Fuel Pump Voltage?

Discussion in '1st Gen. Tacomas (1995-2004)' started by Jclow801, Apr 26, 2016.

  1. Apr 26, 2016 at 10:59 AM
    #1
    Jclow801

    Jclow801 [OP] Active Member

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    2013 Pyrite Mica TRD OR DCSB
    IVD Stage 2, CVT Mt Rainier Pioneer
    I know there's other threads discussing fuel pump (no start) issues. But I can't seem to find anyone with a similar issue...

    I've checked all my relays (except the mysterious one under the dash that I'm not sure exists) But at the same time, I've put a voltmeter to the connector that hooks up to the fuel pump and I'm getting a variety of readings from there. Top left is getting 12 volts, top middle about 6, top right is getting 0, the bottom right (which is the positive leading to the pump) is getting around 6 when you turn the key to the on postion... Bottom left I believe is ground (Attached is a picture of my connector)

    I'm still not hearing anything from the pump even when the pump is getting about 6 volts of power when the key is turned to the on position... Is it supposed to be getting 12 volts? (I've connected a new pump with no change, I've got a 2nd new one that I'll throw in later, but I wanted to get some advice before I do)

    Attached is another picture of the wiring just before the connector to the fuel pump, I cut those and reconnected them using weather proof butt-connectors... I'm still getting the same numbers with them reconnected as I was before I cut and reconnected.

    Any ideas? I'm getting pretty close to taking it to an actual shop.

    20160425_155840.jpg
    20160425_155721.jpg
     
  2. Apr 26, 2016 at 1:41 PM
    #2
    MattFL

    MattFL Well-Known Member

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    Did you check all of your fuses?
     
  3. Apr 26, 2016 at 2:25 PM
    #3
    Jclow801

    Jclow801 [OP] Active Member

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    2013 Pyrite Mica TRD OR DCSB
    IVD Stage 2, CVT Mt Rainier Pioneer
    I will check again... What's the best way to check relays?
     
  4. Apr 26, 2016 at 3:08 PM
    #4
    Dirty Pool

    Dirty Pool FLIES ON THE FRIES, KETCHUPS WATERED DOWN

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    Dirty Pool rear bumper/air tank with integrated spare CV shaft storage, DP customized TJM front bumper, 8000 lb Ramsey/Technora rope, E-locked, Extended breathers with front diff catch can, PCV catch can, SAWs with DP heim joint seals, DP custom 6 leaf rear springs/Billies, DP custom skids, 2lo, Gray wire, Cap, Bed Rug, Black steelies, 01 Center console, Map lights, Disraeli gears
    The crankshaft must be turning on the 3.4 to enable the pump (camshaft on 2.7). Just "ignition on" won't do it.
    "If I just had a nickel for every time i posted this"
    FPDIATEXT_zps68566669_0e725eb5c7cadfe5aeefd1d1bd978304c95749f8.jpg
     
  5. Apr 26, 2016 at 4:58 PM
    #5
    Jclow801

    Jclow801 [OP] Active Member

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    Justin
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    2013 Pyrite Mica TRD OR DCSB
    IVD Stage 2, CVT Mt Rainier Pioneer
    "Iginition on" does send a 3 second signal to the fuel pump.
    Cranking continues to send power.
    My problem is that it's sending only 3 volts in both cases.
    Relay, or its grounding out somewhere?
     
  6. Apr 26, 2016 at 5:31 PM
    #6
    Dirty Pool

    Dirty Pool FLIES ON THE FRIES, KETCHUPS WATERED DOWN

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    59.4 Miles, 56.67° NE Of Moab
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    99 XCAB V6 MT TRD
    Dirty Pool rear bumper/air tank with integrated spare CV shaft storage, DP customized TJM front bumper, 8000 lb Ramsey/Technora rope, E-locked, Extended breathers with front diff catch can, PCV catch can, SAWs with DP heim joint seals, DP custom 6 leaf rear springs/Billies, DP custom skids, 2lo, Gray wire, Cap, Bed Rug, Black steelies, 01 Center console, Map lights, Disraeli gears
    And where did you hear that?
     
  7. Apr 26, 2016 at 5:39 PM
    #7
    Jclow801

    Jclow801 [OP] Active Member

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    2013 Pyrite Mica TRD OR DCSB
    IVD Stage 2, CVT Mt Rainier Pioneer
    My multimeter.
     
  8. Apr 26, 2016 at 5:55 PM
    #8
    Dirty Pool

    Dirty Pool FLIES ON THE FRIES, KETCHUPS WATERED DOWN

    Joined:
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    59.4 Miles, 56.67° NE Of Moab
    Vehicle:
    99 XCAB V6 MT TRD
    Dirty Pool rear bumper/air tank with integrated spare CV shaft storage, DP customized TJM front bumper, 8000 lb Ramsey/Technora rope, E-locked, Extended breathers with front diff catch can, PCV catch can, SAWs with DP heim joint seals, DP custom 6 leaf rear springs/Billies, DP custom skids, 2lo, Gray wire, Cap, Bed Rug, Black steelies, 01 Center console, Map lights, Disraeli gears
    Should be zero volts on the load side of the circuit opening relay/pump power wire until the crank rotates. If you are getting any reading with ignition on, that is a hint at your problem.
    Good luck.
     
  9. Apr 26, 2016 at 6:21 PM
    #9
    Jclow801

    Jclow801 [OP] Active Member

    Joined:
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    Male
    First Name:
    Justin
    Vehicle:
    2013 Pyrite Mica TRD OR DCSB
    IVD Stage 2, CVT Mt Rainier Pioneer
    535978698c073173ede9ebb4b2f0a743_6fc6cee6bcfd3511ebd998bb00196ba3eafc4d4d.jpg

    I'm assuming this is the fuel pump relay socket?
     

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