Auto Shift Manual Control Circuit High Voltage
The P0953 code indicates that the Powertrain Control Module (PCM) has detected a high voltage condition in the auto shift manual control circuit. This circuit is responsible for communicating the driver's manual shift commands (e.g., up/down shifts) from the shift lever or steering wheel paddles to the transmission control module. A high voltage reading typically suggests a short to power, a faulty sensor, or a wiring issue. This can prevent proper manual shifting and may affect transmission operation.
1. Symptoms You Will Notice
- Check Engine Light illuminated
- Inability to manually shift gears (e.g., using paddles or shift lever)
- Transmission stuck in a single gear or default mode
- Reduced fuel economy or performance
2. Most Common Causes
- Short to power in the auto shift manual control circuit wiring
- Faulty shift lever position sensor or switch
- Corroded or damaged connector in the circuit
- Failed PCM or TCM (less common)
3. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for additional codes.
Step 2: Visually inspect the wiring and connectors related to the auto shift manual control circuit for damage, corrosion, or shorts.
Step 3: Test the circuit voltage with a multimeter; compare to manufacturer specifications (typically 5V reference).
Step 4: Check the shift lever position sensor or switch for proper operation and resistance values.
Step 5: If all else is normal, test the PCM/TCM for faults or perform a software update.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is generally not recommended to drive with this code as it may cause unpredictable transmission behavior, such as getting stuck in gear or failing to shift. This can lead to unsafe driving conditions and potential transmission damage.
How much does it cost to fix?▼
The cost to fix P0953 typically ranges from $50 to $150 for diagnostic and simple repairs like cleaning connectors or replacing a sensor. More extensive wiring repairs or module replacement can cost $200-$500 or more.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.