What causes B0688 on a Chevy?

Faulty instrument panel cluster security indicator driver Security indicator circuit shorted to voltage Corroded or loose instrument panel cluster connector Faulty security indicator output in the body control module Water intrusion at the security indicator connector

How do I fix B0688 on a Chevy?

Confirm the code with a scan tool Inspect the instrument panel cluster and body control module connectors Test the security indicator circuit for a short to voltage Command the security indicator with the scan tool and watch the lamp Replace the instrument panel cluster or body control module only after circuit tests pass, then clear the code and retest

Code

B0688

Security system indicator circuit reads high

Q: What does B0688 mean on a Chevy?

B0688. Security system indicator circuit reads high. The body control module cannot light the security indicator and the body warning light comes on.. Applies to Chevrolet, GMC, Buick, Cadillac, Pontiac, Oldsmobile and Saturn models that use this code.

Category: Body
Severity: Body Warning Light
Applies to: Chevrolet, GMC, Buick, Cadillac, Pontiac, Oldsmobile and Saturn models that use this code
Related: No single generic twin. See OBD Codes List

What it means

B0688. Security system indicator circuit reads high. The body control module cannot light the security indicator and the body warning light comes on.. This Chevy-enhanced code applies to Chevrolet, GMC, Buick, Cadillac, Pontiac, Oldsmobile and Saturn models that use this code.

Findings, check these first

Faulty instrument panel cluster security indicator driver
Security indicator circuit shorted to voltage
Corroded or loose instrument panel cluster connector
Faulty security indicator output in the body control module
Water intrusion at the security indicator connector

Standard procedure

Confirm the code with a scan tool
Inspect the instrument panel cluster and body control module connectors
Test the security indicator circuit for a short to voltage
Command the security indicator with the scan tool and watch the lamp
Replace the instrument panel cluster or body control module only after circuit tests pass, then clear the code and retest

Look up another code

Press / to jump to the box. Chevy-enhanced powertrain, body, chassis and network codes.

Sources and review

Review: checked against the recorded source material.

B0688 CHEVROLET Code: Meaning, Causes, and Symptoms | OBD2 Codes - OBD2 Codes
live reference page (obd2-codes.co)
Supports: CHEVROLET and GM-family meaning and likely causes for B0688
Fetched directly. B0688 reads "Security System Indicator Circuit High".
Code B0688 meaning and causes | OBDII.pro
live reference page (obdii.pro)
Supports: independent corroboration of the GM meaning
Fetched directly. obdii.pro is a separate publisher and gives the GM meaning as: Security System Indicator Circuit High More details about the error B0688 and possible reasons for its occurrence.

Last updated 2026-10-10.

Report a correction for B0688. Include your vehicle, the issue and a source if you have one.

This fault sits in the GM theft deterrent system. The GM security codes and Passlock relearn guide covers the families and the relearn cycles.