📖 What Does B0021 Mean?
The B0021 code indicates a malfunction in the Malfunction Indicator Lamp (MIL) circuit, which is responsible for illuminating the 'Check Engine' light on the dashboard. This code is often caused by a faulty MIL bulb, wiring issue, or a problem with the dashboard warning light circuit.
Symptoms
Check Engine light is illuminated, MIL bulb is not functioning, or dashboard warning lights are not working
Common Causes
Faulty MIL bulb, wiring issue, dashboard warning light circuit problem, or a blown fuse
Possible Solutions
1. Check the MIL bulb and replace it if necessary. 2. Inspect the wiring and connectors for damage or corrosion and repair/replace as needed. 3. Check the dashboard warning light circuit for any issues and repair/replace as needed. 4. Check the fuse box for a blown fuse and replace it if necessary.
Recommended Parts & Tools
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📦 Parts Needed
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Frequently Asked Questions about B0021
How serious is B0021?
This code has a medium severity level. This should be diagnosed and repaired soon to prevent further issues.
Can I drive with B0021?
You can typically drive short distances, but have it diagnosed as soon as possible.
How much does it cost to fix B0021?
Repair costs vary depending on the root cause, but typically range from $100-300 including parts and labor.
Related Diagnostic Codes
Other codes that may appear with B0021
Airbag System Malfunction (B0000)
Body System Code B0001: Climate Control Malfunction
Body System Code B0002: Door Locks Malfunction
Body System Code B0003: Windows
Seat Position Sensor Malfunction
Body System Code B0005: Lighting Malfunction
💡 Why These Codes Are Related:
- • Similar Issues: Same root cause or component failure
- • Related Problems: Often occur together due to system interactions
- • Sequential Codes: Progressive failure stages or multiple sensors
- • Same System: Components within the same automotive system