Vehicle Theft Deterrent (VTD) Module Reference Code
Indicates an issue with the vehicle's theft deterrent 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 car's anti-theft system isn't working right, which could lead to false alarms or the car not starting.
What the computer is actually seeing
The VTD module detects a fault or mismatch in the key or immobilizer system, triggering a warning.
What a healthy reading looks like
Key resistance should be between 1.0 to 2.0 ohms when checked with a multimeter; signals from the key should match the expected values in the system.
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.
- 1Check the vehicle key for damage or wear; test the resistance using a multimeter.
- 2Inspect wiring and connectors to the VTD module for corrosion, damage, or loose connections.
- 3Verify battery voltage and condition; ensure it's above 12.4 volts with the engine off.
Common causes
- Faulty key or chip
- Damaged wiring or connectors in the VTD circuit
- Faulty VTD module itself
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code active?
It's not recommended; the car may not start and could leave you stranded.
Will this code come back after clearing?
If the underlying issue isn't fixed, it will likely return.
Why does this code pair with B1611?
B1611 indicates a separate issue with the key or the security system which can also trigger B1655.
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