B1680 — Alarm Panic Input Circuit Short To Ground #

Note: The code label may vary depending on the vehicle manufacturer.

• Alarm Panic Input Circuit Short to Ground (Ford, Lincoln, Mercury)
• Panic Button Input Circuit Low (General Motors)
• Alarm Trigger Circuit Low Input (Chrysler, Dodge, Jeep, RAM)

Summary of code B1680 #

The B1680 diagnostic trouble code (DTC) indicates a problem with the alarm panic input circuit. This circuit is responsible for receiving the signal when the vehicle’s panic button (usually on the key fob or remote) is activated, triggering the vehicle’s alarm. When the control module detects a short to ground—meaning the circuit’s voltage is unexpectedly low, often due to an unintended connection to ground—it logs this code. This issue can prevent the panic alarm from functioning correctly or cause false triggers. Prompt diagnosis is important to ensure both the security system’s reliability and to avoid nuisance alarms.

Common symptoms for code B1680 #

A short to ground in the alarm panic input circuit can manifest in several ways. Drivers might notice the panic alarm not responding, going off unexpectedly, or some warning indicators on the dashboard. The most frequent symptoms include:

• Panic alarm fails to activate when using the key fob or remote
• False alarm triggers without pressing the panic button
• Security system warning lights or messages on the dashboard
• Key fob panic button unresponsive even with new batteries
• Intermittent or persistent alarm sounds

Probable causes for code B1680 #

Several factors can lead to a B1680 code. Most often, the issue is electrical—a direct or indirect connection to ground where there shouldn’t be one. Here are the most common causes, listed in order of likelihood:

1. Damaged or chafed wiring in the panic input circuit, causing a short to ground
2. Faulty panic button switch (either in the key fob or interior switch, if equipped)
3. Corroded or loose harness connectors at the control module or alarm system interface
4. Malfunctioning alarm control module (sometimes called the anti-theft or body control module)
5. Aftermarket alarm or remote starter installation errors

Step-by-step diagnostic for code B1680 #

Diagnosing a B1680 code requires a methodical approach to rule out common causes before considering complex or costly repairs. Here’s a recommended step-by-step process:

• 1. Scan for additional codes to see if other alarm or body system DTCs are also present.
• 2. Inspect the key fob or panic button for obvious physical damage or stuck buttons.
• 3. Locate and visually inspect the wiring and connectors for the panic input circuit, especially near the steering column and under the dashboard.
• 4. Use a digital multimeter to check for continuity and shorts to ground in the panic input wiring.
• 5. Disconnect connectors at the alarm control module (or body control module) and check for corrosion, bent pins, or moisture.
• 6. Test the panic button switch for proper operation, ensuring it isn’t internally shorted.
• 7. If aftermarket systems are installed, verify all splices and integrations are correct and insulated.
• 8. Clear the code and test the system multiple times to confirm repair.

Possible repairs for code B1680 #

The right repair depends on what the diagnostic reveals. Here are the most frequent solutions, each matched to a probable cause:

• Repair or replace damaged wiring that is shorted to ground
• Replace the key fob or panic switch if found to be faulty
• Clean and secure connectors at the control module or alarm interface
• Replace the alarm/anti-theft control module if it fails internal testing
• Reinstall or properly connect aftermarket alarm/remote starter wiring

Is it safe to drive with code B1680? #

Limited: You can usually drive the vehicle safely with a B1680 code, but you may lose panic alarm functionality or experience false alarms. This does not affect core driving systems like brakes or steering. However, if the alarm is sounding unexpectedly or the security system disables the starter, you may experience inconvenience or be unable to start the vehicle. It’s best to address the issue promptly to avoid repeated disruptions or security vulnerabilities.

Vehicles most commonly affected by code B1680 #

While any modern vehicle with a factory alarm system can potentially set a B1680 code, it is most frequently reported on certain brands and models. These include:

• Ford (F-150, Escape, Explorer, Fusion)
• Lincoln (MKZ, Navigator)
• Mercury (Milan, Mountaineer)
• General Motors (Chevrolet Silverado, GMC Sierra, Cadillac Escalade)
• Chrysler, Dodge, Jeep, RAM (Grand Cherokee, 1500, Charger, 300)

Common mistakes & best practices for code B1680 #

Technicians and DIYers sometimes overlook the fundamentals when chasing electrical codes like B1680. Avoid these common pitfalls:

• Replacing the control module too soon without checking wiring and connectors first
• Ignoring aftermarket alarm or remote start wiring that could cause shorts
• Failing to check the panic button switch for sticking or internal shorts
• Not clearing the code and retesting after a repair

Best practice: Always begin with a thorough visual inspection, use a wiring diagram, and isolate the fault before replacing parts. Document all steps for future reference.

Express FAQ for code B1680 #

Here are quick answers to common questions about the B1680 code:

• Q: Can a dead key fob battery cause B1680?
  A: No, a dead fob battery will prevent the panic button from working, but it won’t cause a short to ground. The code indicates an electrical fault in the vehicle’s wiring or switch, not just a power loss.
• Q: Will disconnecting the battery clear a B1680 code?
  A: Disconnecting the battery may temporarily clear the code, but if the underlying fault remains, the code will return. Proper diagnosis and repair are required.