Gate Select Position Circuit Range/Performance
The P0905 code indicates that the transmission control module (TCM) has detected a malfunction in the gate select position sensor circuit, which is used to determine the manual gate position (e.g., PRNDL) in automatic transmissions. This sensor provides feedback on the shifter position, and the code is set when the signal is out of the expected range or performance parameters, often due to electrical issues, mechanical binding, or sensor failure.
1. Symptoms You Will Notice
- Check Engine Light illuminated
- Transmission stuck in one gear or fails to shift
- Erratic or incorrect gear display on dashboard
- Vehicle may not start or shift out of Park
2. Most Common Causes
- Faulty transmission range sensor (TRS) / transmission mode switch
- Open, short-to-ground, or short-to-power in the gate select circuit wiring
- Corroded, loose, or damaged connectors or terminals at the sensor or TCM
- Mechanical misalignment of the shift lever or shift cable
- Internal TCM failure (rare)
3. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for related codes.
Step 2: Visually inspect the gate select position sensor and its wiring for damage, corrosion, or loose connections.
Step 3: Test the sensor's resistance and voltage output per manufacturer specifications.
Step 4: Check the shifter linkage for binding or misadjustment.
Step 5: If all else is fine, test the TCM for proper signal reception.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive with this code as it can cause unpredictable shifting or transmission damage. Have the vehicle diagnosed and repaired promptly.
How much does it cost to fix?▼
The cost typically ranges from $150 to $400, including parts and labor, depending on whether the sensor, wiring, or shifter assembly needs replacement.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.