B1D21 Ford Code - Remote Control Switch Signal Compare Failure
Quick Answer
The Body Control Module (BCM) monitors the Remote Control Switch. Common causes include Faulty Remote Control Switch, Remote Control Switch harness is open or shorted, Remote Control 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
- B1D21 Ford indicates Remote Control Switch Signal Compare Failure.
- Common causes
- Common causes include Faulty Remote Control Switch, Remote Control Switch harness is open or shorted, Remote Control 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 B1D21 Ford Description
What are the Possible Causes of the DTC B1D21 Ford?
- Faulty Remote Control Switch
- Remote Control Switch harness is open or shorted
- Remote Control Switch circuit poor electrical connection
- Faulty Body Control Module (BCM)
How to Fix the DTC B1D21 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 B1D21 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 B1D21 Ford Code
1. What does the OBDII code B1D21 mean on a Ford vehicle?
B1D21 indicates a "Remote Control Switch Signal Compare Failure," meaning the vehicle's module detected a mismatch or fault in the signals from the remote control switches.
2. What are common symptoms of the B1D21 code in a Ford?
Symptoms may include unresponsive remote key fob functions, issues with central locking, or intermittent operation of remote-controlled features.
3. What causes the B1D21 code to appear?
The code can be caused by a faulty remote control switch, damaged wiring, signal interference, or a malfunction in the Body Control Module (BCM).
4. How can I fix the B1D21 code in my Ford?
Inspect the remote control switch and its wiring for damage, replace the key fob battery if necessary, and reprogram or replace the key fob if the issue persists.
5. Can a weak key fob battery trigger the B1D21 code?
Yes, a weak or dead key fob battery can cause signal comparison issues, leading to the B1D21 code.
6. Is it safe to drive with the B1D21 code active?
Yes, the code typically doesn't affect vehicle drivability, but it may impact remote locking and other convenience features.
7. How do I diagnose the B1D21 code?
Use a scan tool to confirm the code, then inspect the key fob, wiring, and BCM for faults. Testing the remote control signal strength may also help.
8. Does the B1D21 code require key fob reprogramming?
In some cases, reprogramming or re-synchronizing the key fob to the vehicle may resolve the issue.
9. Can signal interference cause the B1D21 code?
Yes, external signal interference from devices like cell phones or other electronics can disrupt remote control signals and trigger this code.
10. What should I do if replacing the key fob doesn’t fix the B1D21 code?
If a new key fob doesn’t resolve the issue, inspect the wiring and the BCM, as they may need repair or replacement.
Discuss the causes and fixes for B1D21 Ford OBDII Code
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