P0746: Pressure Control Solenoid A Performance/Stuck Off
The P0746 code indicates that the Powertrain Control Module (PCM) has detected a malfunction in the pressure control solenoid 'A' circuit, which is responsible for regulating hydraulic pressure within the automatic transmission. This solenoid controls line pressure to the clutches and bands, and when it is stuck off or performing incorrectly, the transmission may experience harsh shifting, slipping, or fail to engage gears. The issue can stem from electrical faults, mechanical sticking, or low transmission fluid.
1. Symptoms You Will Notice
- Harsh or erratic shifting
- Transmission slipping or delayed engagement
- Check Engine Light illuminated
- Transmission stuck in limp mode or a single gear
2. Most Common Causes
- Faulty or internally worn pressure control solenoid (PCS)
- Open, short-to-ground, or short-to-voltage in the solenoid electrical circuit
- Corroded, loose, or damaged connectors or terminals in the transmission wiring harness
- Mechanically stuck pressure control valve due to wear or contamination
- Internal transmission valve body failure
- Faulty PCM/TCM (less common but possible)
- Low or degraded transmission fluid level or condition
3. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Check transmission fluid level and condition; top off or replace if necessary.
Step 3: Inspect wiring and connectors for damage, corrosion, or loose connections.
Step 4: Test solenoid resistance and operation using a multimeter and scan tool.
Step 5: If solenoid is faulty, replace it; if fluid is contaminated, perform a transmission flush.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as the transmission may fail completely, leaving you stranded. Short trips to a repair shop are acceptable if shifting is still possible.
How much does it cost to fix?▼
Repair costs typically range from $200 to $600, depending on whether the solenoid alone needs replacement or if a transmission flush and additional labor are required.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.