This service bulletin provides information for dealers/technicians on OnStar Module 2G Sunset Information.
full bulletin at NHTSA ↗2008 Hummer H3 electrical problems
severe 32 complaints filed with NHTSA · avg repair $850 · see electrical across all vehicles →
Failure mileage
Complaints
32
Recalls
0
Avg fix
$850
1crash
4fires
When does it fail?
Of the 32 electrical complaints filed for the 2008 Hummer H3, here's the actual mileage breakdown — failures cluster heaviest at 75,000-100,000 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
Owners have filed 32 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.
Electrical accounts for 28% of all owner complaints filed against this vehicle, across 8 categories tracked.
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 ↗This Preliminary Information communication provides information to the technician about vehicles that have an intermittent no crank, no start, or start stall concern with the security light coming on. Technician may find Diagnostic Trouble Codes B3055, B3060, and/or B3935. Technician should not replace any parts for this concern. If unable to duplicate the concern ask if the customer uses any Radio Frequency Identification Devices when the concern is present. Dealer should also direct their customers to the appropriate section in the Owner manuals that references that the device complies.
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 bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
The passlock anti-theft system is the dominant complaint. Owners describe random no-start conditions where the vehicle won't crank despite a good battery and fresh key fob batteries. The security light may illuminate (a car symbol), or nothing shows at all. Wait 10 to 20 minutes and the vehicle starts normally—until it doesn't start again at random. One owner's vehicle shut off at highway speed. Multiple owners report this failure becoming more frequent over time. Dealers replace the ignition switch and lock cylinder assembly for $300–$600, but owners report the same failure returns within months because the root cause remains unchanged. Owners consistently state they found hundreds of identical complaints online specific to 2006–2010 Hummers and other GM vehicles; GM refuses to acknowledge the issue or recall.
The AC blower motor resistor and wiring harness frequently overheat and melt together, producing burning plastic smells and complete AC failure. Owners observe the burnt resistor in the glove box area. At least one owner saw flames on the battery. Dealers replace both components for several hundred dollars, but recurrence is common. Owners report this happened again within a month of repair in some cases.
Additional electrical failures include door locks that unlock unexpectedly during shifting, a horn that won't work (caused by a failed SIR coil), windshield wipers that quit, and a body control module failure. One owner with a factory tow package discovered melted interior wiring caused by the trailer harness rubbing against sharp body panels.
Same Hummer H3 electrical reports on nearby years: 2006 · 2007 · 2009
Failure modes owners describe
Passlock anti-theft system intermittent no-start
The passlock security system intermittently disables the starter or fuel pump, leaving the vehicle unable to crank. Owners report the vehicle will start after waiting 10-20 minutes while the system resets itself. The issue occurs without warning and the security light may or may not illuminate. No error codes appear in many cases. Some owners report the failure becomes more frequent over time, and in at least one case, the vehicle shut off while driving at highway speeds.
When: Intermittent; can occur at any time when attempting to start the vehicle. Some owners report it happening early (1,000 miles) while others experience it after many years of ownership.
Symptoms owners cite: Vehicle will not crank or start; Security light illuminates (car symbol); No crank/no start with clicking or dead silence; Restarts after 10-20 minutes of waiting; Failure becomes more frequent over time; Vehicle shut off while driving at highway speed (one report); No error codes; Horn blows weakly when key fob unlocks vehicle
Codes mentioned: P1626 (implied from passlock module function)
Repairs/costs cited: One owner replaced ignition switch and lock cylinder assembly for approximately $600, but failure recurred after 4 months. Another owner reports the fix costs $300+ but fails again because the same defective part is reinstalled. Replacing the lock assembly, lock housing, key cylinder, and passlock module was attempted in one case but failure returned.
Recalls/TSBs owners mention: GM refuses to acknowledge the defect or issue a recall. Multiple owners state they found hundreds of online complaints about this exact issue with 2006-2010 Hummers and other GM products. One owner received a recall notification (NHTSA 15V421000) but it addressed visibility, not this issue.
Blower motor resistor and wiring harness melting/burning
The blower motor resistor and heating/air conditioning wiring harness overheat, melt, and burn together. Owners report burning plastic or electrical smells coming from the AC ventilation, followed by complete AC failure. The resistor and wiring harness are visible melted in multiple reports. The failure creates a fire hazard; one owner reports visible flames on the positive battery terminal.
When: Commonly reported at 40,000-90,000 miles. Some failures occur within 2 years of ownership; recurrence after repair is common, with at least one owner experiencing it twice and another reporting a second failure months after repair.
Symptoms owners cite: Burning smell from AC ventilation system; AC stops blowing cold air or becomes intermittent; AC works only on lower speeds; Visible melted or burnt resistor and wiring harness; Smoke from under glove box; Flames visible on battery terminal (one report)
Repairs/costs cited: Dealers replace blower motor and wiring harness. Owners report parts costing several hundred dollars. One owner experienced the same failure two times; another had it recur within one month of repair. Replacement with the factory part does not prevent recurrence.
Recalls/TSBs owners mention: Recall notification NHTSA 15V421000 issued, but parts remain unavailable for repair in multiple reports. Owners state manufacturer has not determined a solution. One owner waited over a month for recall parts with no resolution.
Door locks unlocking unexpectedly
All four doors unlock automatically when the driver shifts into drive or reverse without any warning light or user command. The power master door lock switch also fails to lock the doors properly.
When: Reported at approximately 132,000 miles.
Symptoms owners cite: All four doors unlock when shifting into drive or reverse; No warning light illuminated; Doors unlock when pressing power master door lock switch to lock vehicle
Repairs/costs cited: Vehicle was not diagnosed or repaired.
Ignition switch stuck in ON position
The key becomes stuck in the ignition switch and cannot be turned to OFF. The vehicle cannot be shut down.
When: Reported at 38,000 miles.
Symptoms owners cite: Key stuck inside ignition switch; Unable to turn vehicle off; Defect continues to occur intermittently
Repairs/costs cited: Dealer could not duplicate the defect and performed no repairs.
Body control module failure causing windshield wiper inoperability
The body control module fails, rendering the windshield wipers inoperable. Powering the vehicle off and back on does not restore function.
When: Reported at approximately 81,000 miles.
Symptoms owners cite: Windshield wipers stop working without warning; Failure occurs while driving in rain
Repairs/costs cited: Body control module replacement required.
Horn inoperability caused by failed SIR coil
The horn fails to operate intermittently after the vehicle is driven. Diagnosis revealed a bad SIR (Supplemental Inflatable Restraint) coil causing the horn failure.
When: Failure occurs intermittently every few miles of driving.
Symptoms owners cite: Horn does not operate when pressed; Failure occurs after driving a few miles
Repairs/costs cited: SIR coil replacement required; the part is on special order.
Trailer wiring harness damage from sharp body panels
On vehicles with factory tow package, the trailer wiring harness is routed between sharp body panels and the bumper. Vehicle motion causes the wires to rub against the sharp edges, creating exposure that shorts to the body and causes high current to melt interior wiring.
When: Intermittent failure over approximately 1 year.
Symptoms owners cite: Trailer brakes and lights fail intermittently; Melted interior wiring; Short to body caused by exposed wires
Repairs/costs cited: Problem discovered by owner after removing rear bumper. Shielding wiring and smoothing sharp metal edges can prevent the issue.
Recalls/TSBs owners mention: GM dealer troubleshot the trailer brake and light failures with no solution.
Radiator end tank rupture
The factory radiator end tank ruptures, releasing coolant onto all components under the hood and onto the windshield. The rupture is caused by a defect in the design of the factory radiator.
When: Timing not specified in narrative.
Symptoms owners cite: Radiator end tank ruptures; Coolant sprays on windshield; Coolant released on all engine bay components
Repairs/costs cited: Not specified; owner states this could have caused a much worse situation if it occurred at higher speeds.
Recalls/TSBs owners mention: GM refuses to take action on the radiator design defect.
Multiple electrical failures following wiring harness burnout
After wiring harness burns and is replaced, multiple electrical systems remain non-functional, including radio, air conditioning, and temperature gauge. Security system continues to disable starter.
When: Following replacement of burnt wiring harness.
Symptoms owners cite: Wiring burnt up; Radio does not work after harness replacement; Air conditioning does not work; Temperature gauge does not work; Security system still prevents cranking
Repairs/costs cited: Wiring harness replaced but electrical components remain non-functional.
Battery fire hazard
Flames appear on the positive side of the battery and extend to the oil stick after refueling at a gas station. The fire is extinguished by the owner using a towel.
When: Approximately 132,000 miles; occurs after refilling the gas tank.
Symptoms owners cite: Flames visible on positive battery terminal; Flames extend to oil stick; Abnormal clicking sound when attempting to start; Vehicle fails to start
Repairs/costs cited: Not diagnosed or repaired; vehicle remained at gas station.
Recalls/TSBs owners mention: Dealer and manufacturer not notified.
AC/heating system independent shutdown and repeated failures
The air conditioning and heating system independently shuts off. After repair and recurrence, the vehicle develops additional cascading failures including overheating and failure to start. Burning odor emanates from the AC ventilation. Wire harness melts; blower motor and harness replaced multiple times but failure persists.
When: Initial failure at 90,851 miles; recurrence within months after each repair.
Symptoms owners cite: AC and heating shut off independently; Burning odor from AC ventilation; Vehicle overheats; Vehicle fails to start; Melted wire harness; Wire harness burns/melts after repair
Repairs/costs cited: Blower motor replaced, wire harness replaced, AC charged, radiator inspected, alternator replaced, battery replaced, ignition switch replaced. Multiple repairs performed; failures persist despite repeated dealer visits.
Recalls/TSBs owners mention: Recall notification NHTSA 15V421000 (Visibility) issued but manufacturer states no solution has been determined.
Synthesized from 32 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 3 most recent
Tl* the contact owns a 2008 Hummer h3. While driving approximately 50 MPH with the air conditioning unit activated, there was a burning odor inside the vehicle without warning. The air conditioner failed. The vehicle was taken to the dealer where it was diagnosed that the lower resistor and wiring harness failed, melted together, and needed to be replaced. The vehicle was repaired. The contact…
I looked on the internet to find out why my heater blower was not working and there were lots of complaints about the wiring harness and resistor burning out. I checked mine and sure enough mine was burnt on the wiring harness all the way through the plastic. Gm needs to figure out why it would cause it to malfunction like that cause it could cause a fire. *tr
I was cut off by another driver in rush hour traffic and the horn failed to operate when pressed. After this incident, I discovered that the horn does not work after the vehicle is driven every few miles! The vehicle was in the shop for hours of diagnosis, and finally it was discovered by the technician that the vehicle has a bad "sir coil". The "sir coil" is on special order. *tr
Had electrical trouble with your 2008 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 2008 Hummer H3?
It's a meaningful issue. 32 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 26 complaints that reported odometer mileage, most electrical failures cluster between 62,200 and 100,000 miles, with the median around 81,000. A quarter of owners report trouble before 62,200; a quarter make it past 100,000. 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/2008/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.