Rear window spontaneous failure is the most dramatic complaint. Owners describe their rear hatch glass exploding into hundreds of pieces with violent force while parked, during routine operation, or when closing the tailgate—sometimes with such intensity that glass scatters 20+ feet from the vehicle. One owner's daughter was covered in shards (though not cut), and another's hand was cut by flying glass. No prior damage or warning lights precede these failures.
Windshield wipers exhibit chronic control failure. Multiple owners report wipers turning on when the switch is in the OFF position, either intermittently or running constantly—sometimes for 30+ minutes or the entire drive—especially on vehicle startup. The washer pump activates simultaneously. This problem worsens over time and creates a visibility hazard.
Blower motor resistor melt-down is a fire hazard. Owners report burning odors from vents followed by complete blower failure when the heater resistor module and wiring connector overheat and melt. One owner's harness showed melting at the common wire; another's resistor failed twice in three months. GM issued a recall for this exact defect on the 2006 Sierra 1500 but excluded the Envoy.
Power window switches fail due to corrosion and electrical faults. Front driver-side windows stop operating intermittently or completely; one owner's switch circuit corroded from water intrusion. Door panels also exhibit electrical problems, with one smoking after fuse replacement, indicating internal shorts. Several affected vehicles were explicitly excluded from relevant GM recall campaigns.
Failure modes owners describe
Rear hatch/liftgate window spontaneous explosion
Rear window glass shatters without warning while vehicle is parked or during light operation. Owners report the glass exploding with violent force into hundreds of pieces, sometimes when closing the tailgate or simply during normal use. No prior damage or warning signs noted in most cases.
When: Various mileages; incidents reported as early as routine operation without clear mileage threshold
Symptoms owners cite: Rear window explodes into small pieces with loud noise; Glass fragments scatter 20+ feet; No prior warning lights or symptoms; Sometimes preceded by hinge noise when tailgate operated; Can occur when closing hatch or opening rear door
Repairs/costs cited: Replacement rear window reported at $650
Windshield wipers activate when set to OFF
Wipers intermittently or continuously turn on despite being switched to the off position. Problem escalates over time from occasional spurts to extended operation lasting 30+ minutes, sometimes triggered on vehicle startup.
When: Issues reported starting around 103,000+ miles on some vehicles; began developing in earlier model years per owner searches
Symptoms owners cite: Wipers activate when switch is in OFF position; Windshield washer pump runs simultaneously; Intermittent at first, then progressively worsens; Can run for 30 minutes or longer; Often occurs when vehicle is started; Reduces visibility during operation
Recalls/TSBs owners mention: No recalls or TSBs mentioned for this defect
Front windshield washer nozzles fail to spray effectively
Washer nozzles stop directing fluid in the proper spray pattern, preventing effective windshield cleaning even though fluid is present. This is a recurrent failure—at least one owner experienced the problem twice.
When: First event noted at 32,000 miles; second event occurred later in vehicle life
Symptoms owners cite: Nozzles stop spraying in correct pattern; Fluid flows but does not reach windshield effectively; Reduces visibility in high-debris conditions; Hazard during nighttime driving or when sun creates glare; Problem is not caused by clogging or obstruction
Repairs/costs cited: Required nozzle replacement on first occurrence; recurred after repair
Blower motor resistor and harness melting
Heater blower resistor module and wiring connector overheat and melt, causing burning odor and blower failure. Wiring harness shows melting at the common wire. Owner considers this a fire hazard. A related recall exists for the 2006 Sierra 1500 for this defect, but not applied to the Envoy.
When: Reported around 30,000 miles; second failure on same vehicle occurred within 3 months of first repair
Symptoms owners cite: Strong burning odor from air vents; Heater blower suddenly stops working; Melted wiring connector visible; Relay resistor module damaged; Harness shows melting/heat damage
Repairs/costs cited: Repairs required melted connector and resistor module replacement; part failed again within 3 months
Recalls/TSBs owners mention: Voluntary recall issued for 2006 Sierra 1500 (NHTSA ID unknown) for this defect but not applied to 2006 Envoy
Driver-side door window switch failure
Power window switch stops operating, either intermittently or completely. One case involved water/rain corrosion of the circuit board. Dealer stated replacement of power window devices and controls is needed. Related recalls exist but affected vehicles were not included.
When: Reported at 73,000–170,000 miles depending on vehicle
Symptoms owners cite: Front driver-side window fails to operate; Intermittent operation in some cases; Complete loss of function; Water/rain corrosion noted on circuit board in at least one case
Repairs/costs cited: Power window switch module replacement required; owner cited corrosion due to water/rain leak into circuit board
Recalls/TSBs owners mention: NHTSA Campaign 12V406000 and 15V599000 exist for similar visibility issues on 2006 Envoy but affected vehicles were not included in these campaigns
Rearview mirrors move independently while driving
Both rearview mirrors activate and move on their own during normal driving without driver input.
When: Reported at 98,000 miles
Symptoms owners cite: Both rearview mirrors move independently; Occurs while driving at low speeds (~10 mph); Failure recurs multiple times
Driver-side door panel smoking and fuse failure
Door panel electronics malfunction, causing smoke when fuse is replaced. Fuse blows and smoke ceases, indicating an electrical short or overload in the door panel circuit.
When: Reported at 90,000 miles
Symptoms owners cite: Door panel begins smoking after fuse replacement; Smoke ceases when fuse blows again; Indicates electrical fault in door panel
Repairs/costs cited: Vehicle not repaired; diagnosis not performed
Recalls/TSBs owners mention: NHTSA Campaign 12V406000 (Visibility: Power Window Devices and Controls) did not include this vehicle
AC/heater foul odor on startup
Strong foul smell emits from air vents when AC or heater is turned on, lasting 2–3 minutes before clearing. Manufacturer attributed to high humidity and suggested a dryer unit, but owner disputes this is a design defect.
When: Not specified, but presumed early in vehicle ownership
Symptoms owners cite: Foul odor from vents when AC/heater activated; Lasts 2–3 minutes then clears; Occurs regularly; Does not clear on its own per manufacturer's design philosophy
Repairs/costs cited: Manufacturer quoted $800 for dryer installation; offered 50% discount
Recalls/TSBs owners mention: Manufacturer stated issue is due to high humidity and offered partial reimbursement for aftermarket dryer installation
Synthesized from 24 NHTSA owner complaints — unverified consumer
allegations, summarized for patterns. The verbatim filings appear below.