This preliminary informational (PI) bulletin provides information to dealership personnel that may be helpful when addressing underbody component corrosion with customers.
full bulletin at NHTSA ↗2021 Chevrolet Blazer steering problems
severe 15 complaints filed with NHTSA · avg repair $700 · see steering across all vehicles →
Complaints
15
Recalls
0
Avg fix
$700
1crash
1injury
What stands out
Among the 5 model years of Chevrolet Blazer in our records for steering problems, this one ranks #3 by owner-complaint volume.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering steering 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 service bulletin provides a procedure to add deadener to the batter tray bracket to correct customer concerns of a Service Engine Soon (SES), Reduced Power, Service Brake, Reduced Steering and/or Stabilitrak Message Illuminated on DIC, multiple DTCs.
full bulletin at NHTSA ↗This informational bulletin instructs the tech when fuel/fluid is needed to be tested and where it can be sent for analysis.
full bulletin at NHTSA ↗This service bulletin provides a procedure inspecting for excess grease or Sealant on the Exterior of the steering gear due to seeing grease or sealant on certain locations on the gear.
full bulletin at NHTSA ↗This informational bulletin provides a guide on how to diagnose and test for vibrations utilizing the PicoScope.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
Owners of 2021 Chevy Blazers consistently report a dangerous pattern: a dashboard warning "Steering Assist is Reduced – Drive with Care" followed by either stiff steering or complete power steering lockup while driving at highway speeds (60–70 MPH). One owner experienced full steering failure at 69-70 MPH, veering into the roadway median and deploying airbags; she sustained neck/shoulder soreness, bruising, and PTSD. Disconnecting the battery temporarily restores steering until the fault recurs. OBD readers often show no diagnostic codes.
The root appears tied to a faulty coolant thermostat and temperature sensor (ECT). The 26-gauge ECT wiring runs through the ignition coil harness, picking up electromagnetic interference that produces false temperature readings. This triggers false overheating signals that shut down steering assist, AC, and temperature gauges. The plastic-cased radiator fails prematurely and leaks in identical spots after replacement; one owner replaced both radiator and thermostat twice in 46,000 miles. The plastic casing hides leaks, preventing owner detection of a safety issue.
GM issued Special Coverage N252508350 for thermostat replacement and a Field Service Bulletin with a software patch, but owners report the patch only suppresses ECT failures from being reported—not fixing the underlying electrical design. Dealers report no parts availability for power steering repairs, and multiple owners request a recall, citing online communities of affected 2019–2021 Blazer owners.
Same Chevrolet Blazer steering reports on nearby years: 2019 · 2020
Failure modes owners describe
Steering Assist Reduced warning message with actual steering loss or stiffness
Dashboard warning 'Action Required: Steering Assist is Reduced – Drive with Care' appears while driving. Some owners report the steering wheel becomes stiff or difficult to turn; others report complete power steering lockup at highway speeds requiring towing. No codes often present. Disconnecting the battery temporarily restores function until the next occurrence. One owner experienced catastrophic steering failure at 69-70 MPH, veering into the roadway median and requiring airbag deployment.
When: 15,000 to 31,000 miles; recurring after battery disconnects or resets
Symptoms owners cite: Dashboard warning 'Steering Assist is Reduced'; Steering wheel becomes stiff or hard to turn; Complete power steering lockup; Danger at highway speeds (60-70 MPH); No diagnostic trouble codes present on some vehicles
Codes mentioned: No codes (multiple reports), P0128 (coolant thermostat malfunction)
Repairs/costs cited: Battery disconnect temporary fix. One owner reports power steering gear and power steering module suspected as cause; no parts available and no ETA per dealer. Another owner reports ECT wiring design issue requiring software patch per FSB.
Recalls/TSBs owners mention: Field Service Bulletin addresses ECT wiring fix with software patch. Special Coverage N252508350 covers thermostat replacement on some vehicles. No official recall issued despite multiple requests.
Coolant thermostat and temperature sensor failures
Faulty thermostat and temperature sensor (ECT – Engine Coolant Temperature) trigger false overheating signals. Plastic-cased radiator with aluminum components fails prematurely, leaking in the same location after warranty replacement. ECT wiring (26-gauge two-wire) runs adjacent to high-voltage ignition coil harness, causing electromagnetic interference (EMI) that produces faulty temperature readings. Plastic casing hides leaks from owner detection.
When: Under 10,000 miles after initial replacement; recurring at 24,000–46,000 miles total life
Symptoms owners cite: Cooling fan runs for 5–20 minutes after engine shutdown; Temperature gauge does not register or reads incorrectly (stays at cold); Radiator leaks at same location after replacement; AC stops working when temperature fault detected; Overheating without visible external coolant leaks
Codes mentioned: P0128 (coolant thermostat malfunction)
Repairs/costs cited: Radiator replaced twice under warranty on one vehicle in 46,000 miles. Thermostat replacement needed. One owner estimates radiator-thermostat combo as recurring expensive repair; no specific costs cited. ECT wiring patch is software-based per FSB; does not address root EMI design problem.
Recalls/TSBs owners mention: Special Coverage N252508350 for thermostat replacement. Field Service Bulletin (FSB) addresses ECT wiring with software patch that suppresses ECT failures from triggering steering/AC/gauge inhibits, but acknowledges P0128 can recur. No recall issued.
Power steering electronic control (ESC/PSCM) module failure
Electronic power steering control module or related electrical system fails, causing loss of power steering function. Steering tightens up abruptly; some vehicles show steering messages without diagnostic codes. Failure may be triggered or exacerbated by false temperature sensor signals from the coolant system fault.
When: Low mileage vehicles (15,000–31,000 miles)
Symptoms owners cite: Steering wheel becomes very hard to turn; Steering assist warning message with no codes on OBD reader; Intermittent steering tightness after battery disconnect and reconnect; Failure occurs without warning lights prior to failure event
Codes mentioned: No codes (most reports), P0128 (in some cases)
Repairs/costs cited: One owner reports dealer suspects power steering gear and power steering module; no parts available and no ETA. Temporary restoration by battery disconnect. Another owner notes service shops can reproduce the tightening when error codes appear.
Recalls/TSBs owners mention: No recalls or technical service bulletins specifically addressing ESC/PSCM module failures cited. Field Service Bulletin for ECT wiring may indirectly prevent false steering assist inhibits.
Synthesized from 15 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 3 most recent
P0128, AC not working, Steering Assist Reduced, and Temp Gauge not working. Problem caused by faulty ECT wiring. First the problem is the ECT is a two wire (signal + and -) 26 gauge wire running through the ignition coil wire harness. Ignition coil signals are very high voltage and fairly fast frequency which causes a lot of EMI which is easily picked up on a 2 wire voltage based wire set. The…
In September 2023, when getting my vehicle serviced for a routine oil change, I was told there was a leak in my radiator. They replaced the entire thing under warranty. On November 15th, 2025, while driving on the highway heading home from out of town with my children, an error flashed up saying “steering assist is reduced – drive with care” Upon arriving home, the fan on my car was running on…
Steering assist reduced message comes on and temperature guage goes down to cold not working and after you shut car off fan runs full force for 10 minutes. Shows no check engine light or no codes.
Had steering trouble with your 2021 Chevrolet Blazer?
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 steering problem on the 2021 Chevrolet Blazer?
It's a meaningful issue. 15 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $700.
At what mileage does the steering typically fail?
Based on the 15 complaints filed, steering issues most often appear around 24,000 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
What does it cost to fix?
Independent shops typically charge around $700 for steering 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 steering?
No active recalls currently cover steering 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/2021/Chevrolet/Blazer.
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.