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B1688moderate severity✨ AI-generated

Keyless Entry / Ignition Switch Fault

There’s an issue with the keyless entry or ignition switch system.

Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.

What it means (plain English)

The computer is not getting a signal from the keyless entry or ignition switch when you try to start the vehicle or unlock it.

What the computer is actually seeing

The Body Control Module (BCM) looks for a voltage signal from the keyless entry switch or ignition switch. If it doesn't see a stable 10-12 volts when the switch is pressed, it throws this code.

What a healthy reading looks like

Expected voltage from keyless entry switch is 10-12 volts; should have continuity when pressed.

Guided diagnostic — the DiagCoach way

Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.

  1. 1Check battery voltage. It must be above 10 volts before proceeding.
  2. 2Inspect wiring and connectors for corrosion, damage, or looseness. Repair as needed.
  3. 3Using a multimeter, check the voltage at the keyless entry switch. It should read between 10-12 volts.
  4. 4If voltage is correct, test the switch for continuity while pressing it. If no continuity, replace the switch.
  5. 5If all checks out, check the BCM for proper programming and issues.

Common causes

  • Faulty keyless entry or ignition switch
  • Damaged wiring or connectors
  • Low battery voltage (below 10 volts)
  • BCM programming issue

Typical repair cost

$$$

Related codes

Frequently asked questions

Can I still drive the vehicle?

Yes, but you may have issues with starting the vehicle or using the keyless entry features.

Will the code come back if I clear it?

If the underlying issue isn't resolved, the code will likely return.

Why does this code appear alongside another code?

Codes may appear together if they're related to the same electrical system malfunction.

Working a real vehicle right now?

Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.

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