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Thread: IQ3 + USM, wont communicate with ECU

  1. #1

    Default IQ3 + USM, wont communicate with ECU

    I am having trouble with my new haltech IQ3 Dash. I have it installed with a USM and the cars runs off a haltech ps2000 ecu. It will not read any channels from the ecu. I installed everything according to this bulletin from haltech: ... -Cable.pdf
    I have all the correct cables, and terminator cap etc.

    It does communicate with the usm. I have a brake pressure sensor on the USM and it reads fine.

    If I jump the usm out of the system and run the Haltech IQ3 cable directly from the dash to the ecu it reads the ecu channels.

    Does anyone have any clue?

  2. #2

    Default Re: IQ3 + USM, wont communicate with ECU

    Found the problem, wiring got knicked during install.

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