B2172 Ford Code - Inertia Switch Input Circuit Open
Quick Answer
With the engine running, the Battery Power OFF (BPO) function may be triggered by the front and/or rear Inertia Fuel Shut OFF (IFS) switches opening, a high-voltage interlock circuit opening, the Electrical Interlock (EL I) circuit opening (fuse protected by the battery junction box) or if the contactor box within the Battery Control Module (BCM) requests a BPO mode. Common causes include Faulty Inertia Fuel Shut OFF (IFS) Switch, Inertia Fuel Shut OFF Switch harness is open or shorted, Inertia Fuel Shut OFF Switch circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- B2172 Ford indicates Inertia Switch Input Circuit Open.
- Common causes
- Common causes include Faulty Inertia Fuel Shut OFF (IFS) Switch, Inertia Fuel Shut OFF Switch harness is open or shorted, Inertia Fuel Shut OFF Switch circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code B2172 Ford Description
What are the Possible Causes of the DTC B2172 Ford?
- Faulty Inertia Fuel Shut OFF (IFS) Switch
- Inertia Fuel Shut OFF Switch harness is open or shorted
- Inertia Fuel Shut OFF Switch circuit poor electrical connection
- Faulty Battery Control Module (BCM)
How to Fix the DTC B2172 Ford?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the B2172 Ford code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Frequently Asked Questions about B2172 Ford Code
1. What does the OBDII code B2172 on a Ford vehicle mean?
The B2172 code indicates an "Inertia Switch Input Circuit Open," which means there’s an issue with the circuit connected to the inertia fuel shutoff switch.
2. What are the common symptoms of the B2172 code in Ford vehicles?
Symptoms include the engine not starting, stalling after a collision, and potentially a check engine light or other warning lights on the dashboard.
3. What causes the B2172 code to appear?
Common causes include a faulty inertia switch, damaged wiring or connectors in the circuit, or a blown fuse related to the fuel system.
4. What is the function of the inertia switch in Ford vehicles?
The inertia switch cuts off the fuel supply in the event of an accident to reduce the risk of fire.
5. Can I reset the inertia switch to clear the B2172 code?
Yes, pressing the reset button on the inertial switch may resolve the issue if it was triggered accidentally, but further diagnosis is recommended if the code persists.
6. How do I locate the inertia switch in my Ford vehicle?
The inertia switch is typically located under the dashboard, near the passenger-side kick panel, or in the trunk area, depending on the model.
7. Is the B2172 code serious and should I address it immediately?
Yes, it should be addressed promptly as it can prevent the engine from starting or stall the vehicle, posing safety risks.
8. Can a blown fuse cause the B2172 code?
Yes, a blown fuse in the fuel system circuit can cause an open circuit and trigger the B2172 code.
9. How can I diagnose the B2172 code in a Ford vehicle?
Inspect the inertia switch, wiring, and connectors for damage or disconnection, and test the circuit with a multimeter to check for continuity or voltage issues.
10. Do I need a professional mechanic to fix the B2172 code?
While some issues like resetting the inertia switch can be done by the driver, diagnosing and repairing wiring or component faults may require a mechanic's expertise.
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