Park Signal with Vehicle Moving
The B2237 code indicates a logical inconsistency where the vehicle reports being in Park while the Vehicle Speed Sensor (VSS) detects motion. Under normal operation, the Park signal should be inactive when the vehicle is moving. This fault suggests a problem in the shift lever circuit, Transmission Control Module (TCM), or Body Control Module (BCM) that processes these signals. The system flags this as a fault because it represents an impossible state during normal driving.
1. Commonly Affected Makes
2. Most Common Causes
- Faulty park/neutral position switch
- Damaged or corroded wiring in the harness between the shift lever and control module
- Misadjusted or mechanically damaged shift lever mechanism
- Faulty BCM that processes the Park signal
- Short circuit or open circuit in the Park signal line
3. Symptoms You Will Notice
- Check Engine Light or transmission warning light illuminated
- Vehicle may not start in Park or start in other gears
- Transmission may not shift properly or stay in Park
- Cruise control may be disabled
4. Step-by-Step Diagnosis
Scan for additional codes and verify B2237 is present
Inspect the park/neutral position switch and its wiring for damage or corrosion
Check for proper operation of the shift lever mechanism
Test the Park signal circuit for shorts or opens using a multimeter
If wiring and switch are OK, suspect TCM or BCM failure and perform module-specific tests
5. Frequently Asked Questions
Is it safe to drive?▼
It is generally safe to drive short distances, but the vehicle may exhibit shifting issues or fail to start. Have it diagnosed soon to avoid potential transmission damage.
How much does it cost to fix?▼
Repair costs typically range from $100 to $500, depending on whether the issue is a simple switch replacement or a more complex module repair.