This service bulletin provides information for dealers/technicians on OnStar Module 2G Sunset Information.
full bulletin at NHTSA ↗2006 Hummer H3 electrical problems
severe 90 complaints filed with NHTSA · avg repair $850 · see electrical across all vehicles →
Failure mileage
Complaints
90
Recalls
0
Avg fix
$850
19fires
1injury
When does it fail?
Of the 90 electrical complaints filed for the 2006 Hummer H3, here's the actual mileage breakdown — failures cluster heaviest at 0-25,000 mi.
0-25k
25-50k
50-75k
75-100k
100-125k
125-150k
150k+
Each bar shows the share of total complaints filed at that mileage range. Peak failure window highlighted. Some owners report problems earlier; some make it well past 150,000 miles symptom-free. Maintenance habits and driving conditions shift the curve as much as mileage alone.
What stands out
Of the 5 model years of Hummer H3 we track for electrical problems, this one carries the most owner complaints on file — 90.
Owners have filed 90 electrical complaints with NHTSA against this vehicle, but no formal recall covers the issue — the federal record reflects what manufacturers have admitted, not everything owners are reporting.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering electrical on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
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 starting/charging tester and Vehicle Data Recorder tools, giving website address and step by step instructions to complete the update.
full bulletin at NHTSA ↗Vehicle 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 updating affected modules (with some exceptions). The updating of modules is completed in parallel instead of the technician needing to update one module at a time. This allows a more streamlined approach for dealers and customers.
full bulletin at NHTSA ↗This service bulletin provides information for dealers/technicians on Service Programming System (SPS) Error Codes E4398, E4399, E4401, E4403, M4404, M4413, M6954, M6955, E4414, E4423, E4491, E4492, or E6961 and resolution information.
full bulletin at NHTSA ↗The intent of this service bulletin is to identify aftermarket ALDL or DLC interface devices as potential sources for causing multiple customer concerns that do not have other diagnostic methods to identify them.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
Owners describe a vehicle plagued by electrical failures that create genuine safety hazards. The most common and dangerous complaint centers on the blower motor resistor and wiring harness under the glove box: these components overheat, melt, produce burning smells and smoke, and in several reported cases, ignite fires while the vehicle is being driven. Multiple owners say they've replaced the same part three, four, or more times in a few years because the failures keep recurring—the replacement uses the same defective design. In the worst incidents, the fire spread rapidly and the vehicles became total losses.
The Passlock anti-theft system is another persistent headache. It randomly refuses to let you start the engine, displaying a key symbol on the dash and forcing a 10–15 minute wait before the system resets. Some owners report this happens nearly half the time they try to start. GM has no fix and claims not to know about it, though hundreds of owners report the identical issue online.
Water intrusion from the sunroof creates a third category of electrical damage: drain tubes clog or fail, water pours into the interior and dashboard, shorts out the CPU and blower controller, and leaves everything corroded and smelly. Dealership drain cleaning is temporary—leaks resume within days.
Additionally, owners report complete loss of electrical power and engine stalling while driving at highway speeds, dashboard lights going dark without warning, wiring failures in multiple locations, and stuck ignition keys. These are not isolated incidents—owners stress that online searches reveal widespread complaints across H3 forums and other Hummer models.
Same Hummer H3 electrical reports on nearby years: 2007 · 2008 · 2009
Failure modes owners describe
Blower motor resistor and wiring harness overheating/melting
The blower motor resistor pack and associated wiring harness under the glove box overheat and melt, creating burning odors, smoke, and occasionally fires. The resistor terminals and connector pins burn, short out, and weld together. Multiple owners report replacing the same part multiple times as failures recur.
When: Typically triggered by activating heater or A/C in cold or warm weather; failures range from early operation to higher mileage (50k–160k miles). Some failures happen within days of previous repairs.
Symptoms owners cite: Burning plastic smell from under dashboard/glove box; Smoke inside cabin or visible under glove compartment; Blower motor ceases to work on any fan speed; Melted resistor terminals and connectors visible upon inspection; Fire ignition under dashboard (in severe cases)
Repairs/costs cited: Owners and dealers replace blower motor resistor pack (part number 11221007.011 or AC Delco 15-80647) and wiring harness connector. Costs cited: $26–$325+ depending on labor. Dealers report having this part in stock due to frequency of failures. Replacement does not prevent recurrence.
Recalls/TSBs owners mention: NHTSA Campaign 15V421000 issued for visibility-related wire damage; parts reportedly unavailable or out of stock for extended periods. GM acknowledged the issue to some owners but refused out-of-warranty claims. No design change implemented; replacements use same defective design.
Passlock anti-theft system malfunction
The security/anti-theft system (Passlock) triggers false alarms, displaying a key symbol on the dashboard and disabling engine starting. System thinks the vehicle is being stolen. Owners must wait 10–15 minutes for the system to reset before the vehicle will start. Some owners report it occurs on nearly 50% of start attempts.
When: Intermittent, no clear pattern tied to mileage or temperature, though some note more frequent issues after several years of ownership.
Symptoms owners cite: Key symbol appears on dashboard; Engine cranks but will not start; All other electrical systems (radio, lights) work normally; Waiting 10–15 minutes allows normal restart; Recurring after reset; No warning in owner's manual
Repairs/costs cited: GM advises replacing the ignition switch, but this is expensive and does not guarantee a fix. Some owners report replacing fuel pumps and other components without resolving the core issue.
Recalls/TSBs owners mention: GM has no official fix or recall. GM customer service claims unfamiliarity with the problem despite hundreds of online reports. No TSB or warranty program identified.
Sunroof drain tube blockage causing water intrusion and electrical short-outs
Sunroof drain tubes become blocked or fail to direct water properly. Water leaks into the cabin, soaking carpets, headliner, and pillar panels. Water entry causes CPU and blower controller shorts, corroded metal parts, and burned wires. One owner reported OnStar and interior lights failing when water poured in during driving; vehicle had to be towed. Dealership repairs are temporary; leaks resume within days.
When: Occurs during and after rainy weather; one owner's vehicle caught fire when water shorted electrical components while driving.
Symptoms owners cite: Water leaking down interior pillars and into dash compartment; Soaked carpet on both driver and passenger sides; Water-damaged headliner; OnStar system shutting off; Interior lights dimming; CPU and blower controller shorts; Burned wires and rusted metal components; Persistent damp smell inside vehicle
Repairs/costs cited: Dealership "cleaning" or unclogging drain tubes at $300 per visit; repairs are temporary. No permanent solution identified. Owner states technician told him off-record that nothing will permanently fix the design flaw.
Recalls/TSBs owners mention: Dealership acknowledges the issue but offers only temporary fixes. GM directed owner to dealership with no permanent remedy offered. No recall identified.
HVAC control module intermittent operation and illumination
HVAC controls malfunction intermittently. Dashboard climate control lights illuminate erratically or all at once (all three environmental control lights blink together). Fan responds unpredictably to settings. Recirculate mode cannot be selected; all lights blink five times then stop when attempted.
When: Occurs after heater/A/C activation; one case triggered shortly after replacing burned resistor.
Symptoms owners cite: Climate control lights illuminate without command; Fan speed increases or decreases without input; Inability to select recirculate mode; All three environmental control knobs' lights blinking in unison; Intermittent heater/A/C operation
Repairs/costs cited: One owner diagnosed burned resistor female blade receptacle on wiring harness as the cause; replaced resistor and harness but recirculate mode remained inoperative.
Dashboard and instrument cluster lighting intermittent or complete failure
Instrument cluster lights go out without warning while driving, leaving driver unable to see speedometer or gauges. Lights suddenly reappear minutes later. Owner reported safety concern: no visibility into vehicle speed or state during failure.
When: Occurred around 4 years of ownership; one event lasted several minutes while driving.
Symptoms owners cite: All in-dash lights extinguish; Speedometer/gauges unreadable; Lights spontaneously return after minutes; No warning or pattern
Electrical power loss and stalling at highway speed
Vehicle loses all electrical power while driving at highway speeds. Engine stalls, power brakes and steering fail, radio dies, all lights go out. Vehicle can restart after stopping and waiting. Some owners report this occurs nearly every time they drive extended distances on the highway.
When: Occurs during highway driving at high speeds; one owner reported at least three dozen incidents over months of ownership.
Symptoms owners cite: Complete loss of all electrical power and engine power; Engine stall; Power steering failure; Power brakes failure; Radio/lights go out; Vehicle restarts after waiting; Dashboard warning lights illuminate (stability system, check engine, reduced power, ASC failure)
Repairs/costs cited: Dealers unable to duplicate the problem during diagnostic testing despite frequent owner occurrence. One case noted wiring over engine failed and needed replacement; another noted computer controlling all electrical functions was replaced without resolving the issue.
Brake lights and turn signals failure
Brake lights and front/rear turn signals fail to illuminate when activated. Control module may need replacement per dealer diagnosis.
When: Occurred around 140,000 miles; failure recurred multiple times.
Symptoms owners cite: Brake pedal depressed but brake lights do not illuminate; Front turn signals fail to illuminate; Rear turn signals fail to illuminate; Recurring failures
Repairs/costs cited: Dealer diagnosed control module as needing replacement.
Ignition switch key stuck or failed to release
Key becomes lodged or stuck in the ignition and cannot be removed or turned. Requires force or dealer intervention to extract.
When: Occurred at 65k–126k miles; recurring over months in some cases.
Symptoms owners cite: Key cannot be extracted from ignition; Instrument panel lights constantly illuminate; Airbag warning light illuminates (in one case)
Repairs/costs cited: Dealer diagnoses tunnel ignition or ignition switch replacement as remedy; repairs not completed in reported cases.
Wiring harness and connector failures throughout vehicle
Wiring harnesses fail in multiple locations—under the dashboard (heater/A/C), under the driver's seat, and over the engine. Connections burn, melt, and short. One owner reported wires burned upon water intrusion from sunroof.
When: Varies by location; under-dash failures triggered by heater/A/C activation; some failures occur at lower mileage, others at 50k–160k+ miles.
Symptoms owners cite: Burning odor from specific areas; Smoke from dashboard or under seats; Melted connector terminals; Burned wire insulation; Loss of function in associated systems
Repairs/costs cited: Individual harness sections replaced; costs depend on location and labor. No comprehensive fix addresses underlying wiring design issues.
Recalls/TSBs owners mention: NHTSA Campaign 15V421000 addresses visibility wire harness issues; parts frequently unavailable.
Oil consumption abnormally high after 90,000 miles
Engine begins consuming oil rapidly without visible leaks. Owner must refill every 2–3 weeks; approximately $30–$60 monthly in oil purchases.
When: Onset around 90,000 miles; ongoing issue.
Symptoms owners cite: Rapid oil consumption; No visible oil leaks; Oil burning internally; Frequent refilling required
Synthesized from 90 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 9 most recent
Heating/ ac fan blower harness burnt up. A very common problem on an Hummer h3/. *tr
Vehicle locked up while I was driving - unable to start and had to have towed to dealership. Serious electrical problems for the 2nd time. *jb
While driving vehicle locked up and shut down - could not restart and had to have the vehicle towed to the dealer. *jb
Tl* the contact owns a 2006 Hummer h3. The contact stated that the vehicle failed to start intermittently. All the warning indicators illuminated on the instrument panel. The vehicle was taken to Cadillac of naperville (located at 1507 ogden ave, naperville, il 60540, (630) 355-2700) where diagnostic testing was completed, but a failure code could not be found. The vehicle was not repaired. The…
Tl* the contact owns a 2006 Hummer h3. The contact stated that while driving approximately 35 MPH, the dashboard caught on fire from the passenger's side of the heater. The vehicle was taken to the dealer, who diagnosed that the harness, resister fan motor, replay, heater hoses and baffle fan needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the problem. The…
Blower motor recall issue. Burning electrical odor coming from behind the glove compartment. Coincides with the blower motor connector recall. This cannot be resolved soon enough.
This will be the third blower motor resistor that I have had to replace. This time I am replacing the harness because it burned up so badly on two terminals. Gm has yet to acknowledge this problem... I paid $26 for the resistor, and it's going to be $30 for the harness, and I save a ton on the labor because I am a mechanic, but this is a potential fire hazard. There is an air flow in this area,…
Pass lock system prohibits truck from starting. Have to wait 10 minutes when it decides to work. This is an ongoing issue. For the amount of money this truck cost this should not be happening consistently.
11/02/11 smell of something burning looked under dash blower resistor and plug melted together had replaced on 12/11/11 smelt burning plastic again had same problem blower resistor and plug melted again from what I understand it is a on going problem in this vehicle gm should be responsible in fixing it before there are major fire damage or a death. *tr
Had electrical trouble with your 2006 Hummer H3?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the electrical problem on the 2006 Hummer H3?
It's a meaningful issue. 90 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $850.
At what mileage does the electrical typically fail?
Across the 76 complaints that reported odometer mileage, most electrical failures cluster between 62,108 and 118,000 miles, with the median around 90,344. A quarter of owners report trouble before 62,108; a quarter make it past 118,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $850 for electrical repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to electrical?
No active recalls currently cover electrical issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2006/Hummer/H3.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.