← View Generic B1166 Guide Severity: Medium
🚗 Vehicle-Specific Guide

This guide is customized for your 2020 Chevrolet SILVERADO 1500 PICKUP

B1166: B1166: Body Control Module (BCM) Security System Malfunction

on 2020 Chevrolet SILVERADO 1500 PICKUP

Fix Cost
$100 - $500
Parts & Labor
Difficulty
3/5
1-2 hours
DIY Possible?
❌ No
Pro recommended
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 B1166 Mean on 2020 Chevrolet SILVERADO 1500 PICKUP?

The Body Control Module (BCM) has detected a security system malfunction, likely due to a faulty sensor, wiring issue, or software problem.
⚠️

Symptoms

  • • Keyless entry system failure
  • • alarm system malfunction
  • • or immobilizer system failure
🔍

Common Causes

  • • Faulty BCM sensor
  • • wiring issue between BCM and sensor
  • • software glitch
  • • or faulty immobilizer system
🛠️

How to Fix B1166 on 2020 Chevrolet SILVERADO 1500 PICKUP

Check BCM sensor connections and wiring for damage or corrosion Clear any stored trouble codes and perform a system reset Update BCM software if necessary Replace faulty BCM sensor or immobilizer system if necessary

🔧

Need Maintenance Info for Your SILVERADO 1500 PICKUP?

Get oil capacity, filter specs, and torque settings for your specific 2020 Chevrolet SILVERADO 1500 PICKUP.

View 2020 Chevrolet SILVERADO 1500 PICKUP Specs

Parts for 2020 Chevrolet SILVERADO 1500 PICKUP

BCM sensor Shop ↗ wiring harness Shop ↗ immobilizer system Shop ↗

Essential Tool

Must Have

OBD2 Scanner

Read & clear codes on your 2020 Chevrolet SILVERADO 1500 PICKUP

Shop Scanners ↗
🔗

Related Diagnostic Codes

Other codes that may appear with B1166

B1164 Sequential Code

B1164: Seat Position Sensor Circuit Malfunction

Medium
B1165 Sequential Code

B1165: Body Control Module (BCM) Lighting Circuit Malfunction

Medium
B1167 Sequential Code

B1167: Audio System Malfunction

Medium
B1168 Sequential Code

B1168: Airbag System Circuit Malfunction

High

💡 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