← View Generic B0021 Guide Severity: Medium
🚗 Vehicle-Specific Guide

This guide is customized for your 2020 Chevrolet SILVERADO 1500 PICKUP

B0021: B0021: Malfunction Indicator Lamp (MIL) Circuit Malfunction

on 2020 Chevrolet SILVERADO 1500 PICKUP

Fix Cost
$50 - $200
Parts & Labor
Difficulty
3/5
1-2 hours
DIY Possible?
✅ Yes
Save money
Your Vehicle
2020 Chevrolet
SILVERADO 1500 PICKUP
⚠️

Important for 2020 Chevrolet SILVERADO 1500 PICKUP Owners

Before starting repairs, verify which engine your 2020 Chevrolet SILVERADO 1500 PICKUP has. Check your VIN or engine code to ensure you order the correct parts.

📖 What Does B0021 Mean on 2020 Chevrolet SILVERADO 1500 PICKUP?

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.
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Symptoms

  • • Check Engine light is illuminated
  • • MIL bulb is not functioning
  • • or dashboard warning lights are not working
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Common Causes

  • • Faulty MIL bulb
  • • wiring issue
  • • dashboard warning light circuit problem
  • • or a blown fuse
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How to Fix B0021 on 2020 Chevrolet SILVERADO 1500 PICKUP

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.

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Parts for 2020 Chevrolet SILVERADO 1500 PICKUP

MIL bulb Shop ↗ wiring harness Shop ↗ dashboard warning light circuit Shop ↗

Essential Tool

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Related Diagnostic Codes

Other codes that may appear with B0021

B0019 Sequential Code

B0019: Power Window Circuit Malfunction

Medium
B0020 Sequential Code

B0020: Seat Switch Circuit Malfunction

Medium
B0022 Sequential Code

B0022: Immobilizer System Malfunction

Medium
B0023 Sequential Code

B0023: Audio System Fault

Medium

💡 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