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For 1990-2009 cars only
Makes 🢒 HUMMER 🢒 2008 🢒 H2 🢒 Bulletins 🢒 Loss of High Speed LAN Communications, IPC Warning Lights On, DIC Messages, No Crank, IPC Gauge Drop or Fluctuation, Door Lock Cycling, Hard Transmission Shift, DTCs Set

Loss of High Speed LAN Communications, IPC Warning Lights On, DIC Messages, No Crank, IPC Gauge Drop or Fluctuation, Door Lock Cycling, Hard Transmission Shift, DTCs Set

Subject:Loss Of High Speed GMLAN Communications, IPC Warning Lights On, DIC Messages, No Crank, IPC Gauge Drop or Fluctuation, Door Lock Cycling, Hard Transmission Shift, DTCs U0073, U0100, U0101, U0102, U0109, U0121, U0132, U0140, U2100 Set (Inspect Identified Electrical Connections and Wiring for Faults)

Models:2008 HUMMER H2


Condition

Some customers may comment on one or more of the following symptoms:

    • Instrument panel gages drop or fluctuate.
    • Multiple service messages displayed on the DIC (Drivers Information Center).
    • Various instrument panel warning lights on.
    • Door locks cycle while driving.
    • No crank.
    • Vehicle shifts hard or defaults to 2nd or 3rd gear.

Upon investigation, the technician may find one or multiple communication codes, such as DTC U0073, U2100, U0100, U0101 U0102, U0109, U0121, U0132, U0140 set as current or in history.

Correction

If you experience one or more of the symptoms above, please review the following areas for a possible concern.

  1. Inspect the EBCM connector for loose terminals or low pin retention at pins 8, 9, 23, and 24. These pins are for circuits 2500 and 2501 for high speed GMLAM communications with the EBCM, TCM, and ECM. Please use the proper test tool when checking pin tension. The proper test tool for this EBCM is J-35616-64B, which should be supplied in your terminal test kit. If the pins are loose or damaged, replaced all 4 pins with new terminals (part number #7116-3703-02 located in tray 14 of the GM terminal repair kit).

    2. Object Number: 2043300 Size: SH

    Object Number: 2043301 Size: SH
  2. Inspect the transmission pass-through connector for loose or low pin retention at pins 10, 11, 13, and 14. Also make sure these pins are fully seated into the connector. See photos above for location and photo that shows a terminal that was not full seated into the transmission connector. Repair as needed.

    3. Object Number: 2043302 Size: SH

    Object Number: 2043303 Size: SH
  3. Check for a pinched/cut wiring harness where the transmission harness is attached to the transmission. The metal attachment clip may be cutting into the harness and shorting the high speed GMLAM circuit to ground. (Location and style of clip is shown in photos above) Repair as needed.
  4. Check for chaffed or shorted wiring by the park brake bracket assembly to the left IP junction block.
  5. Inspect underneath the underhood bussed electrical center (UBEC) for pinch or chaffed wires on the UBEC support bracket.

    6. Object Number: 2077437 Size: SH
  6. Check connector X1 (1) on the back of the left IP fuseblock for a loose connection. Reports from the field have found the connector not fully seated and causing intermittent concerns. See photo above for location.

Warranty Information

For repairs performed under warranty, use the applicable published labor code and information.