Below is a comprehensive diagnostic guide for P0571 on the 2018–2023 Honda Accord. Based on the provided NHTSA-data excerpt, there were no owner complaints and no recalls for this make/model/year/issue combination. No recalls found in NHTSA database.
CODE MEANING AND SEVERITY
- What P0571 means: P0571 is an OBD-II diagnostic code indicating a fault in the Cruise Control/Brake Switch A circuit (or the cruise control input circuit, depending on the labeling used). In practical terms, it signals an out-of-range or intermittent condition in the signal that tells the engine computer (ECU/PCM) the status of the brake switch or cruise-control main switch.
- Severity and impact:
- Cruise control: Typically disabled or unable to engage while the fault is present.
- Brake switch interaction: If the brake switch circuit is involved, the brake lights and brake switch input to the ECU may be affected; this can also disable cruise control and might cause intermittent warning indicators.
- Driveability: In most cases, the car should remain drivable; this code mostly affects cruise control functionality rather than normal propulsion. However, if the brake switch is faulty, a warning light could appear and shifting between modes may be impacted.
- Important note: Since no recalls exist in the data provided, P0571 on this specific Accord model year is not tied to a known NHTSA recall. If you see other brake or powertrain codes, address those first, as they can mask or aggravate the P0571 condition.
COMMON CAUSES ON HONDA ACCORD
- Faulty brake pedal switch (brake light switch) or misadjusted switch.
- Faulty cruise control main switch/stalk assembly or poor electrical connection to it.
- Wiring harness damage or corroded/loose connectors in the brake switch circuit or cruise control wiring.
- Bad or intermittent circuit in the ECU/PCM, or a problem with the cruise control module if equipped.
- Low battery voltage or poor charging (voltage dips can trigger signal faults).
- Poor or loose grounds/grounding points in the cruise control or brake switch circuits.
- Fuse or fusible link related to the cruise control or brake switch circuit.
- Moisture or corrosion in connectors, especially under-hood or behind the steering wheel assembly.
- Note: These are common automotive causes based on typical Honda cruise control/brake switch circuits and general diagnostic practice. They are not tied to any specific TSB in the provided data.
SYMPTOMS
- Cruise control will not engage, or disengages immediately after being set.
- Cruise control indicator light may be off, but the fault is stored in the PCM.
- Brake lights function normally or illuminate when the pedal is pressed (depending on the exact fault location).
- Inconsistent or intermittent loss of cruise control functionality.
- Other DTCs may accompany P0571 (see “Related Codes” below).
DIAGNOSTIC STEPS
Note: The steps are written to be practical and repeatable without assuming dealer tools beyond a standard OBD-II scanner and basic hand tools.
Step 1: Confirm with a scan
- Use an OBD-II scanner to read PCM stored/ pending codes and freeze-frame data.
- Confirm P0571 is present and note any accompanying codes (especially P0570, P0572, or other cruise-control related codes).
Step 2: Verify brake switch operation
- With the ignition on (engine off), observe brake lights as you press and release the pedal. The brake lights should illuminate when the pedal is pressed.
- If brake lights do not behave normally, inspect the brake light switch at the pedal. Adjust or replace if the switch is out of position or faulty.
- If possible, monitor the brake switch signal (A circuit) with a multimeter or scan tool; typical expectation is a change in signal when the pedal is pressed versus released. Check for intermittent signals or resistance indicating a bad switch or wiring.
Step 3: Inspect the cruise control switch (stalk) circuit
- Inspect the cruise control master switch/stalk wiring and connector for corrosion, bent pins, or loose connection.
- Check continuity from the stalk to the PCM in the A (or cruise input) circuit if you have wiring diagrams and appropriate tools.
Step 4: Inspect wiring and connectors
- Inspect the harnesses and connectors in the brake switch and cruise control circuits for damage, pinch points, or corrosion.
- Pay attention to areas near the steering column, underhood harness routing, and near the brake pedal.
- Re-seat connectors and apply dielectric grease to prevent future corrosion.
Step 5: Check power supply and grounds
- Test the battery voltage and charging system to ensure a stable 12.6 V+ with engine off and 13.5–14.8 V with engine running.
- Inspect relevant ground points for cleanliness and tightness; a poor ground can cause intermittent sensor signals.
Step 6: Check fuses and modules
- Inspect fuses related to cruise control and brake switch circuits; replace blown fuses.
- If you have access to live data, look for abnormal signals in the brake switch input or cruise control input to the PCM.
Step 7: Test in a controlled scenario
- After performing the above checks, clear codes and perform a road test to see if P0571 returns under the same conditions (e.g., when engaging cruise on a straight road with moderate speed).
Step 8: Consider additional diagnostic steps if needed
- If P0571 persists after brake switch and cruise switch/wiring checks, there may be a more subtle ECU/PCM input issue or a faulty brake switch control circuit that requires more advanced diagnostics or replacement.
- In cases where no physical fault is found, reprogramming or software updates from a dealer may be considered if a service bulletin exists (note: not cited here due to the data provided).
RELATED CODES
- P0570: Cruise Control Input Circuit (general fault indicating the PCM did not receive a valid signal from the cruise control input).
- P0572: Cruise Control/Brake Switch B Circuit (secondary circuit related to the cruise control or brake switch).
- P0573, P0574 (less common on some systems): Other variants in the cruise control/brake switch family.
- If multiple cruise control/brake switch-related codes appear, address the lowest-numbered or most consistently active circuit first, then re-test.
REPAIR OPTIONS AND COSTS (2025 PRICES)
Prices are ballpark estimates based on typical repair shops and common Hondas. Actual prices vary by region, labor rate, and whether you use OEM vs aftermarket parts.
Brake light switch replacement (brake pedal retrofit/adjustment)
- Parts: $10–$40
- Labor: 0.5–1.0 hours
- Estimated total: $70–$180
Cruise control main switch/stalk replacement
- Parts: $25–$120
- Labor: 1.0–2.0 hours
- Estimated total: $150–$400
Wiring harness/connectors repair or replacement (short, damaged wiring)
- Parts: $5–$100 (depends on length and connector type)
- Labor: 1.0–2.5 hours
- Estimated total: $150–$500
Brake switch circuit repair (including fuses, grounds, or connector refurbishment)
- Parts: typically minimal (fits with brake switch or connectors)
- Labor: 0.5–1.5 hours
- Estimated total: $80–$250
ECU/PCM related repair or replacement (rare and usually not the first fix)
- Parts: $300–$900 (likely dealer or specialized shop)
- Labor: 1.0–2.0 hours plus possible programming
- Estimated total: $600–$1500
- Note: In many cases ECU reflash or programming is required if a controller fault is suspected.
Brake light failure or bulb replacement (as part of the diagnostic process)
- Parts: $1–$15
- Labor: minimal if self-installed; otherwise 0.25–0.5 hours
- Estimated total: $20–$60
Tips:
- If the brake switch is the root cause, replacing it is usually quick and inexpensive.
- If the cruise switch, wiring, or ECU is involved, costs can rise quickly due to labor and possible need for programming.
DIY VS PROFESSIONAL
- DIY-friendly tasks:
- Replacing a faulty brake light switch (often accessible near the brake pedal).
- Checking brake lights for proper operation and basic inspection of the switch.
- Inspecting visible wiring and connectors for obvious damage or corrosion.
- Replacing a fuse and cleaning connectors (with proper safety precautions).
- Tasks you may want a professional for:
- Replacing the cruise control switch or stalk, especially if it involves disassembly of the steering wheel area.
- Diagnosing intermittent electrical faults behind the dash or inside the PCM harness.
- Any required ECU programming or reflash.
- Complex wiring repairs or harness replacements that require wiring diagrams and specialized tools.
Safety note: When working around airbags, steering columns, or pedal assemblies, disconnect the battery and wait a few minutes before servicing; airbags can deploy even if the vehicle is off.
PREVENTION
- Regularly inspect the brake pedal switch for proper operation and alignment; adjust as needed.
- Keep battery and charging system healthy; voltage dips can trigger false fault codes.
- Periodically inspect and clean electrical connectors in the brake switch and cruise control circuits; apply dielectric grease to protect against corrosion.
- Ensure all fuses related to cruise control and brake circuits are in good condition and properly seated.
- Keep wiring neat and free from pinches or abrasion; avoid moisture buildup around the steering column and pedal areas.
- Address any brake system issues promptly; a faulty brake switch that causes intermittent signals can lead to cascading faults in related systems.
- If you notice intermittent cruise control operation, investigate electrical connections and battery health before replacing modules.
Final notes on data limitations
- The provided data states: No owner complaints found in NHTSA for this make/model/year/issue, and no recalls found in NHTSA database. This means the guide avoids citing specific recalls or complaint trends for this exact combination. The diagnostic guidance above relies on general automotive practice for P0571 and Honda cruise control/brake switch circuitry, not on any specific NHTSA-verified recall or complaint pattern.
- If you have additional symptoms or other codes, re-run diagnostics with those in mind, as multiple issues can coexist and influence each other.
If you'd like, I can tailor a more detailed step-by-step diagnostic flowchart based on the exact symptoms you’re seeing (e.g., just a cruise control issue, brake warning light on, or intermittent signal).