The 2024 Cadillac Lyriq has accumulated 15 brake-related complaints spanning several distinct failure modes. The most serious involve complete loss of brake response: owners report brake pedals becoming entirely unresponsive during parking maneuvers at 3 mph, low-speed traffic stops at 5–10 mph, and once at 70 mph on a freeway. In these cases, drivers applied brakes firmly or repeatedly with no effect, and vehicles coasted into obstacles or other cars. One owner experienced sudden braking and smoking brakes with a dashboard warning at highway speed, forcing shutdown and towing.
Unexpected automatic emergency braking is also reported—one instance at 70 mph on a straight, dry road with no traffic ahead. Conversely, AEB and forward collision alerts failed to activate during actual low-speed collisions.
Other owners describe pulsing ABS behavior during normal braking, especially during transitions from regenerative to friction braking, with dealers acknowledging reproduction but offering no fix. Rear sensors fail during reversing and backing in rain. A few owners report dashboard messages ("Brake System Failure," brake overheating warnings) requiring hard pedal pressure or resulting in speed limits of 43 mph.
GM issued recall 24V589000 for Brake System Control Module software updates on certain 2023–24 Lyriq models due to brake-control performance issues. However, multiple owners report GM investigations concluded "no defects found" without providing supporting technical data, and several dealerships lack EV service capability entirely.
Failure modes owners describe
Loss of Brake Response or Complete Brake Failure
The brake pedal becomes unresponsive, requiring hard or repeated pedal pressure to achieve any stopping effect. In several cases, brakes failed entirely at low speeds (3-10 mph) during parking or low-speed collisions, and once at 70 mph on a freeway. Owners report the vehicle coasting forward without deceleration despite firm brake application.
When: Low speed (3-70 mph), parking maneuvers, and low-speed traffic situations; one case at highway speeds with ~3,300 miles; multiple instances across mileage range
Symptoms owners cite: Brake pedal unresponsive to normal or firm pressure; Vehicle coasts forward despite brake application; No stopping effect or severely reduced braking; Repeated brake pumping ineffective; Vehicle continues forward into obstacles or other vehicles
Codes mentioned: NHTSA Campaign 24V589000 (Service Brakes, Hydraulic), ABS system failure (reported by dealer in one case)
Repairs/costs cited: One owner had ABS system addressed under recall 24V589000. Other cases remain unresolved; dealers unable to replicate or find faults; some dealerships lack EV service capability.
Recalls/TSBs owners mention: NHTSA Campaign 24V589000 (Brake System Control Module software update for possible brake-control performance issues); one case linked to this campaign. Multiple owners report GM denial of defects without supporting data or technical analysis.
Unexpected or Unwanted Automatic Emergency Braking (AEB) Activation
AEB engages without driver input or a valid safety threat. One owner reports the system activated at 70 mph on a straight, dry road with no traffic ahead; another at 3-4 mph during normal reversing. In some low-speed failure cases, AEB failed to activate when needed.
When: Highway speeds (70 mph), low-speed reversing, and parking situations
Symptoms owners cite: AEB engages without collision hazard; Dashboard alerts (yellow Forward Collision warning, red heads-up display warnings); Sudden braking without driver input; AEB fails to activate when vehicle fails to brake during collisions
Repairs/costs cited: No repairs documented for unwanted AEB activation. In collision cases, AEB non-activation was not explained by dealers or GM.
Recalls/TSBs owners mention: No documented manufacturer response or TSB for unwanted AEB activation.
ABS Pulsing and Inconsistent Behavior During Regenerative Braking Transition
ABS engages unexpectedly during normal braking when transitioning from one-pedal driving (regenerative) to friction braking. Owner reports pulsing sensation and unpredictable stopping behavior. Dealers confirmed reproduction of the issue but claimed vehicle is 'operating as designed.'
When: Intermittently during normal driving, particularly during regenerative-to-friction braking transitions; began shortly after vehicle delivery
Symptoms owners cite: Unexpected ABS activation during normal braking; Pulsing sensation during braking; Inconsistent and unpredictable braking behavior; Reduced braking confidence; No warning lights or messages
Repairs/costs cited: Multiple dealer visits; issue reproduced but no fix provided. Owner told vehicle 'operating as designed.'
Recalls/TSBs owners mention: Issue escalated to GM with no resolution provided.
Brake Overheating and Safety System Shutdown
At 70 mph during rush-hour traffic, brakes overheat, triggering automatic braking. Brakes begin smoking and emit odor; dashboard warning 'brakes overheating, do not drive, call service' appears. Rear collision system goes offline. Vehicle requires immediate shutdown and towing.
When: ~3,300 miles (approximately 2 months old), highway driving at 70 mph during heavy traffic
Symptoms owners cite: Brakes begin smoking and smell; Brake overheating warning message; Rear collision system goes offline; Unexpected automatic braking engagement
Repairs/costs cited: Vehicle towed to dealership; dealership lacks EV service capability and unable to diagnose or repair.
Recalls/TSBs owners mention: No documented manufacturer response.
Brake System Failure Message with Hard Brake Requirement
Dashboard displays 'Brake System Failure' message. When this occurs, driver must apply brakes very hard to achieve stopping, and even then the vehicle may not stop completely. Speed is limited to 43 mph. Message appeared three times in less than one month.
When: Multiple occurrences within one month at unspecified mileage
Symptoms owners cite: Brake System Failure message on display; Requires very hard brake application to slow vehicle; Vehicle may not stop completely; Speed limited to 43 mph when message active
Repairs/costs cited: No repairs documented.
Recalls/TSBs owners mention: No documented manufacturer response.
Rear Sensor and Auto-Braking Failure During Reversing
Rear-view safety sensor alert and auto-braking system fail to function during reversing. Vehicle crashes into a tree. In another case, during rain, vehicle unexpectedly slams on brakes while reversing, making backing maneuvers take 3-4 minutes and creating hazards with other vehicles.
When: Reversing operations; rain conditions trigger issue during backing maneuvers
Symptoms owners cite: Rear-view safety sensor alert does not function; Auto-braking safety sensor does not activate; Vehicle crashes during reversing; Unexpected braking during backing in rain; Excessive braking force during reverse maneuvers
Repairs/costs cited: Case denied by manufacturer; no documents provided to owner.
Recalls/TSBs owners mention: Manufacturer denied case; owner denied access to decision documents.
Spurious Brake Activation with TPMS Warning Light
Brakes independently activate at speeds under 35 mph on multiple occasions. TPMS warning light illuminates intermittently. One front passenger-side tire was flat. Software update applied but issue persisted.
When: Multiple occasions under 35 mph; approximately 7,000 miles
Symptoms owners cite: Independent brake activation at low speeds; TPMS warning light illuminated intermittently; Flat tire
Repairs/costs cited: Software update applied; repair did not resolve issue.
Recalls/TSBs owners mention: Manufacturer notified; undisclosed system software update issued but ineffective.
Synthesized from 15 NHTSA owner complaints — unverified consumer
allegations, summarized for patterns. The verbatim filings appear below.