ABS light, no speedo, trans light blinking

Discussion in '99+ 7.3L PowerStroke Engine & Drivetrain' started by dboyw, Jun 28, 2017.

  1. dboyw

    dboyw Full Access Member

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    As the title says. I replaced the rear abs/speed sensor with no change, then I replaced the front abs sensors and still no change. Truck still drive great, only difference I feel is when coming off of the throttle, there is a hard down shift. Trans was replace several years ago with a BTS trans.

    My favorite garage is unable to read the computer due to his snapon scanner being stolen so I wanted to ask here first before I go to another garage for diagnostic work.

    Thanks
     
  2. 01yellerCobra

    01yellerCobra Full Access Member

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    With the no speedo I wonder if the speed sensor died? Or maybe the wiring was damaged. I can see the ECU having issues if it doesn't know how fast the vehicle is moving.

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  3. BIG JOE

    BIG JOE Full Access Member

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    What he said.
     
    Last edited: Jun 28, 2017
  4. JLDickmon

    JLDickmon ursus combibo

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    The sensor in the pig is common, but what a lot of guys fail to check is the connector itself. The wires can fail in the insulation breaking contact. I've seen it more than once.
     
  5. jobaa

    jobaa SDD Junior Member

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    I had the same issue with my 2000. I flogged it for a long time replacing the speed sensors several times. The problem was intermittent so it was very difficult to nail down. I finally found that the wire from the frame to the differential speed sensor was parted within it's housing and was causing the problem. I soldered it back together and used some marine grade heat shrink. Problem solved. I hope this helps.
     
  6. dboyw

    dboyw Full Access Member

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    Still working on this. I was able to check wiring from sensor to plugs under hood and they check out good, I tested with my volt meter for continuity. Another shop that read the computer says computer cannot see the rear speed sensor. So it is wiring somewhere, or I was wondering if it could be the ABS pump/relay stopping the signal.
     
  7. Kodadd

    Kodadd SDD Junior Member

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    try the diff speed sensor my speedo we crazy and wouldn't shift diff speed sensor fixed it. Good luck
     

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