Owners of the 2006 Buick Rainier report a cluster of electrical failures ranging from minor nuisances to life-threatening fires. The most severe complaints involve underhood and dashboard fires—several owners describe sudden smoke and flames appearing while driving or while the vehicle sat parked, with at least two vehicles fully engulfed before fire departments arrived. In these cases, fires either originated near the headlight wiring or driver-side power window switches, or emerged from the dash with no warning. Owners also report chronic starting and stalling issues: engines shutting off at highway speed or refusing to start after multiple attempts, with dealers suspecting (but not confirming) ignition switch problems. A pattern of melted wiring harnesses has been documented by independent mechanics, and one owner's driver-side wiring harness melted while the vehicle sat idle. Power door locks, power windows, and HVAC controls malfunction erratically—some fail outright, others work intermittently. Fuel gauge readings are unreliable, showing empty when the tank is full, triggering check-engine lights. One owner reports headlights cycling off and on while driving. An anti-theft warning light remains illuminated in at least one case even after key-fob and manual start attempts. Dealers have been unable to diagnose root causes in most instances, and some have denied recall applicability despite owners receiving GM recall notices.
Failure modes owners describe
Vehicle fire / electrical fire in dash and underhood
Uncontrolled fire originating in the dashboard or headlight/power window switch areas, destroying vehicles completely. At least two vehicles burned while being driven; one burned while parked and idling. Fire departments responded; no injuries reported in the complaints.
When: While driving at highway speed; while idling in driveway; within 9 months of purchase for one owner
Symptoms owners cite: White and black smoke entering the cab from above and below the dash; Burning electrical smell; Smoke and flames visible underneath dashboard; Smoke and melted components visible in power window panel area; Burning embers falling into the cab
Repairs/costs cited: Vehicles destroyed by fire; not repaired. One independent mechanic found melted driver-side wiring harness.
Melted wiring harness
Driver-side wiring harness melted, rendering the vehicle inoperable. Discovered when vehicle was lifted onto tow truck.
When: Approximately 168,000 miles
Symptoms owners cite: Vehicle failed to start; Remote key fob would not unlock doors; Anti-theft warning light remained illuminated; Wiring harness visibly melted
Repairs/costs cited: Wiring harness required replacement; vehicle not repaired.
Ignition switch failure / engine stall and no-start condition
Engine stalls unexpectedly while driving or at idle; vehicle refuses to start or requires multiple start attempts. Dealer suspected ignition switch; some complaints reference GM recall campaign 12V406000 (Electrical System, Visibility) without confirmation of actual cause.
When: Approximately 112,000 miles; failure recurred multiple times; vehicle stranded for 5+ hours at one location
Symptoms owners cite: Engine stalls while driving at any speed; Vehicle will not start after key insertion or key-fob attempts; Vehicle eventually restarts on its own at highway speed; requires neutral at low speed; Anti-theft warning light or passenger-side airbag warning light illuminated intermittently; Burning odor present
Repairs/costs cited: Dealer recommended ignition switch, various wires, and throttle body replacement; vehicle not repaired by owner. Independent mechanic replaced ignition switch for $300.
Recalls/TSBs owners mention: GM recall campaign 12V406000 (Electrical System, Visibility) applies to at least one VIN in these complaints.
Power door lock and power window failure
Power door locks and power windows malfunction intermittently or fail completely. One owner reports door module, power door lock, and power window switches on driver's side became inoperative.
When: Intermittent failures; complete failure at unspecified mileage
Symptoms owners cite: Power door locks fail to unlock via remote key fob or manual attempt; Power windows jam and will not operate up or down; Driver-side door module completely dead—no locks, no windows, no function; Door latches will not open or close
Repairs/costs cited: Driver-side door module replacement cost $422; part was ordered.
HVAC control malfunction
Air conditioning and heating controls work erratically or not at all. In one case, the AC suddenly activated at full force without user input, immediately before the vehicle caught fire.
When: Chronic, at unspecified mileage; sudden activation occurred on March 14, 2015 while driving
Symptoms owners cite: Heating and cooling controls non-responsive or intermittent; Air conditioner suddenly activated full force without user input
Repairs/costs cited: Dealer claimed no problem could be found during initial inspection.
Fuel gauge malfunction
Fuel gauge displays erratic readings, showing empty when tank is full or near full. Check engine light also triggers in conjunction with false empty warnings.
When: Occurs after refueling
Symptoms owners cite: Fuel gauge reads zero and tank-empty warning light illuminates after refueling; Check engine light illuminates 2–3 miles after false empty warning; Fuel gauge returns to actual level after 10–15 miles of driving; Warning reappears when tank is at approximately 1/4 full
Headlight failure and wiring issues
Low-beam headlights cycle off and on intermittently while driving. Headlights have been replaced multiple times. One fire complaint cited headlight wiring or switch area as the fire origin.
When: Intermittent while driving at night; headlights replaced twice at unspecified mileage
Symptoms owners cite: Low-beam lights go off intermittently while driving and eventually come back on; High beams and other lights unaffected; Repeated headlight failures requiring replacement
Repairs/costs cited: Headlights replaced twice; fire-origin investigation cited headlight wiring or switch area.
Wiper and washer fluid activation by itself
Windshield wipers and washer fluid spray activate on their own without user input. Owner references a 2004 recall for Trailblazers with the same issue and mentions Takata recall.
When: Occurred during rain while driver's wife was driving
Symptoms owners cite: Windshield wipers activate automatically; Washer fluid sprays without being engaged; Multiple activations reduced visibility during rainy conditions
Recalls/TSBs owners mention: Owner references a 2004 Trailblazer recall for this issue; Takata recall mentioned.
Complete electrical system shutdown while driving
All electrical systems failed simultaneously while the vehicle was in motion on an interstate highway, leaving the driver without lights or other functions.
When: While driving on Interstate 75
Symptoms owners cite: Vehicle lost all electrical power—no lights, no instruments; Engine stopped
Repairs/costs cited: Ignition replaced at cost of $300.
Recalls/TSBs owners mention: Owner questioned whether model should be included in GM recall.
Violent jerking while driving with concurrent power window and fuel leak
Vehicle jerked violently without warning during highway driving; concurrent power window jam and fuel leak also occurred.
When: Approximately 105,000 miles
Symptoms owners cite: Violent jerking at 40 mph; Power windows jammed up and down; Fuel leaked onto ground
Repairs/costs cited: Vehicle not diagnosed or repaired.
Synthesized from 16 NHTSA owner complaints — unverified consumer
allegations, summarized for patterns. The verbatim filings appear below.