2004 Hummer H2 electrical system problems
14 owner complaints filed with NHTSA name the electrical system on the 2004 Hummer H2 — 24% of all complaints for this model year.
What owners report
“Odometer Fraud. The contact purchased a 2004 Hummer H2. The contact discovered a mileage discrepancy after the purchase. The vehicle was a private sale. At the time of purchase, the vehicle mileage was 200,000. It was later discovered that the mileage on the Title was 210,000. Additionally, the…”
filed Feb 10, 2026
“Yesterday I turned off the alarm and unlocked the doors via the keypad. I opened the driver door and my wife opened the passenger rear door and the Hummer H2 started. No key in the ignition and the fob does not have a start button. I then got in the car and inserted the key and turned the key to ON…”
filed Feb 22, 2022
Verbatim excerpts from complaints filed with NHTSA. Reports are not independently verified.
Related service bulletins
This Preliminary Information communicates to the dealer the process for downloading or updating operating software for the Tire Pressure Monitor, Active Fuel Injector tester, multi media tester, PICO Scope, GR8…
PIP4723J · Service Bulletin/Repair Instructions · issued Oct 25, 2024Vehicle Wide Programming (VWP) is a new process to update software on GM Vehicles. It provides the ability via a single selection within Techline Connect to first identify which modules need updating and then proceed to…
General Communication · Service Campaign · issued Aug 26, 2024
Electrical System problems in other H2 years
| Year | Reports | Share |
|---|---|---|
| 2006 H2 | 4 | 18% |
| 2005 H2 | 27 | 34% |
| 2003 H2 | 24 | 17% |
Other reported problem areas on the 2004 Hummer H2
Counts are unique NHTSA complaints naming this component group. Complaints are unverified owner reports; mileage is computed only from complaints that included a usable odometer reading.