Theft Deterrent System Signal Failure
Indicates a problem with the security system signal.
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 computer isn't getting the right signal from the anti-theft system, which could mean the system is acting up or there's a wiring issue.
What the computer is actually seeing
The vehicle's computer expects a specific signal pattern from the theft deterrent system. If this pattern is missing or outside of expected voltage levels (typically 0-5V), it triggers the code B2655.
What a healthy reading looks like
The expected signal should show a stable voltage between 0.5V and 2.5V when the system is armed, with no interruptions.
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.
- 11. Check the battery voltage. It should be at least 12.4V with the vehicle off and 13.7V to 14.7V with it running. If voltage is low, charge or replace the battery.
- 22. Inspect the wiring and connectors related to the theft deterrent system for any signs of wear, corrosion, or damage. Repair or replace as necessary.
- 33. Use a scan tool to check for related codes. Look for any additional faults that may indicate a broader problem with the security system.
- 44. Verify the functionality of the key fob. Replace the battery and check for proper operation with a spare fob if available. If both fobs fail, suspect the vehicle module.
- 55. If wiring is intact and key fob works, replace the theft deterrent module.
Common causes
- Faulty theft deterrent module
- Damaged wiring or connectors in the security system
- Battery voltage issues affecting the module operation
- Key fob issues or faults
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's best to avoid driving the vehicle as the anti-theft system might fail, potentially leaving you stranded or unable to start the vehicle.
Will this problem come back after repairing?
If fixed properly, it shouldn't come back unless there's a new electrical issue or module fault.
Why does this code pair with other codes?
It often indicates a systemic issue with the security system, which can affect multiple components, causing various faults to trigger.
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