Honda Civic: Common Codes & Fixes
Real-world diagnostic data for the Honda Civic. These are the codes techs see most often. Tap any code for the full vehicle-specific fix and the exact part.
45 codes have specific fixes for the Honda Civic
B0081 B0081 (seat belt pretensioner circuit) on Honda is usually the driver-side pretensioner at the B-pillar. C1651 Honda sets C1651 when the brake fluid reservoir level switch reads low or open. P0026 Bank 1 intake rocker arm oil control solenoid sticks closed, dropping intake VTC response. P0030 Honda O2 sensor heater failure is common above 100K miles. P0031 Upstream (sensor 1) oxygen sensor heater circuit develops high resistance as the sensor ages past 100K miles. P0036 The post-cat O2 sensor on Honda vehicles sits in a corrosion-prone location behind the catalytic converter. P0053 Extremely common on aging Civics — upstream air/fuel sensor heater resistance rises out of spec. P0054 Downstream O2 sensor heater resistance code — usually a simple sensor replacement after 100K miles. P0054 Downstream O2 heater circuit high resistance, often following a catalytic converter replacement with a non-OEM unit. P0076 Bank 1 intake valve control solenoid low side driver circuit open. P0077 Intake VTC high-side circuit fault — diagnose with DVOM across the solenoid pins (should be 6.7-7.5 ohms at 68F). P0117 Honda ECT circuit low — replace the ECT sensor (near the upper radiator hose) with Honda OEM. P0118 ECT high voltage after cooling system service — common when the sensor connector isn't fully seated. P0133 Test the upstream A/F sensor with live data -- it should respond to throttle changes within 100ms. P0139 Downstream O2 slow response on Honda — replace with Denso OEM sensor. P0140 Replace downstream (post-cat) O2 sensor with Denso OEM. P0300 Start with spark plugs (NGK Iridium ILZKR7B11). P0304 Perform a coil swap test first. P0335 The CKP sensor is behind the crank pulley near the oil pump. P0403 The EGR valve lift sensor circuit on the D17 engine develops high resistance from heat cycling. P0420 Often a downstream O2 sensor (sensor 2) rather than the cat itself. P0457 P0457 specifically points to a fuel cap issue as the source of the EVAP leak. P0497 P0497 indicates low EVAP purge flow. P0498 P0498 on Honda means the canister vent shut valve circuit has low voltage. P0500 Honda uses a transmission-mounted VSS. P0502 Low vehicle speed sensor signal on the Honda Civic is often caused by a corroded connector at the transmission. P0505 The IACV (idle air control valve) gets clogged with carbon deposits. P0506 Idle speed drops below target on Honda K-series engines due to a dirty throttle body. P0530 The A/C refrigerant pressure sensor fails and sends an out-of-range signal to the ECM. P0700 P0700 on Honda often points to the transmission range switch (Neutral safety switch) or a failed torque converter lockup solenoid. P0715 The mainshaft (input) speed sensor on Honda automatics develops cracked housings that allow fluid to reach the connector. P0720 The countershaft (output) speed sensor on Honda automatics is located on the front of the transmission. P0731 Gear 1 incorrect ratio on Honda automatics almost always indicates low clutch pack wear or a stuck 1st gear clutch control solenoid. P0734 4th gear ratio fault on Honda 4-speed and 5-speed automatics indicates 4th clutch pack failure. P0741 TCC stuck off or performance issue is extremely common on Honda automatics. P0750 Shift solenoid A (SS-A) failure on Honda automatics causes harsh 1-2 shifts or no first gear. P0751 Shift solenoid A performance issues on Honda automatics are caused by solenoid coil resistance drift or varnish restricting solenoid… P0760 Shift solenoid C (SS-C) on Honda automatics controls overdrive engagement. P0770 Shift solenoid E on Honda automatics controls pressure regulation for smooth shift quality. P0785 Shift/timing solenoid faults on Honda automatics indicate a problem with the linear solenoid that controls shift timing and feel. P1129 P1129 on Honda = MAP sensor signal high or lean O2 swapped. P2097 Contaminated or aged downstream O2 sensor reads falsely rich. P2414 Replace upstream A/F ratio sensor (Denso OEM Honda). P2646 Low oil or wrong-viscosity oil prevents the VTEC rocker actuator from engaging. U1206 U1206 lost comm with immobilizer/key module on Honda typically means the transponder key isn't being read. U1207 U1207 lost comm with door module on Civic is almost always a broken wire in the driver's door harness where it enters the A-pillar.
Frequently Asked Questions
What are the most common check engine light codes on a Honda Civic?
The most commonly reported OBD-II codes for the Honda Civic include B0081, C1651, P0026, P0030, P0031. Each code indicates a specific issue -- tap any code above for the full diagnostic breakdown.
How much does it cost to fix a check engine light on a Honda Civic?
Repair costs vary by code. Many Honda Civic fixes like gas cap replacement, sensor cleaning, or spark plug changes are under $50 in parts and can be done at home. More complex repairs like catalytic converter or transmission work can run $500-$2,000+ at a shop.
Can I drive my Honda Civic with the check engine light on?
It depends on the code. A steady check engine light usually means you can drive short distances safely. A flashing check engine light means stop driving immediately -- continued driving can cause serious engine damage. Scan the code first to know what you are dealing with.