P0747 on 2017-2022 Chevrolet Camaro: Pressure Control Solenoid 'A' Stuck On Causes and Fixes

What's Unique About the 2017-2022 Chevrolet CAMARO

The 2017-2022 Camaro, part of the sixth generation, primarily uses GM's 8-speed (8L45/8L90) or 10-speed automatic transmissions. The 8-speed units, in particular, are the subject of multiple Technical Service Bulletins (TSBs) and class-action lawsuits for issues including harsh shifting, shudder, and internal failures. The P0747 code is a well-documented symptom of these underlying issues. TSBs confirm that GM has been investigating this code since at least 2016, often relating it to internal hydraulic pressure loss, valve body wear, or TCM calibration anomalies, not just a simple solenoid failure. 🎬 Watch: Troubleshooting P0747 and the Pressure Control Solenoid A. The solenoids and valve body components are flow-rated and must be programmed to the TCM, making component swaps complex.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Symptoms You May Notice

• Harsh or jerky shifting, sometimes feeling like being rear-ended. [3, Bulletin #N242480631-04, 24]
• Check Engine Light or Malfunction Indicator Lamp is on. [Bulletin #PIP5425A]
• Reduced engine performance or vehicle entering 'limp mode', often stuck in a single gear. [Bulletin #N242480631-04, 10]
• Transmission slipping between gears.
• Delayed engagement when shifting into Drive or Reverse.
• Vehicle may not move at all, or revs without moving before slamming into gear.
• Transmission overheating warning.
• A noticeable 'shudder' or vibration during light acceleration, which can be a precursor to this fault (related to TSB 18-NA-355).

Most Likely Causes

1. Faulty Transmission Valve Body 🔴 High Probability → Shop Transmission Valve Body Wear in the valve body bores, particularly the signal accumulator piston bores and feed limit valves, is a very common failure point on 8L45/8L90 transmissions. This wear causes hydraulic pressure leaks, which the TCM misinterprets as a stuck solenoid. Transmission specialists confirm this is far more common than an actual solenoid failure.
   How to confirm: A technician can perform advanced pressure testing. Visual inspection of the valve body after removal may show scoring or wear in the bores. Often, the only confirmation is replacing the valve body and seeing if the problem is resolved.
   Typical fix: Replacement of the entire valve body assembly, followed by a service fast learn procedure and TCM reprogramming to characterize the new components. Some specialists can ream the bores and install oversized valves.
   Est. part cost: $600-$1500 for a new valve body assembly.
2. Low or Contaminated Transmission Fluid 🟡 Medium Probability → Shop Transmission Assembly The original factory-fill fluid in many 8-speed transmissions was found to be hygroscopic (absorbs moisture), leading to a well-known 'shudder' issue described in TSB 18-NA-355. This degraded fluid can contribute to varnish buildup and cause valves and solenoids to stick. Metal shavings from internal wear also contaminate the fluid, clogging passages.
   How to confirm: Check the transmission fluid level and condition. The fluid should be red and clear, not brown, black, or smelling burnt. A fluid flush with the updated Mobil 1 Synthetic LV ATF HP fluid is the first step for the shudder issue and may sometimes temporarily resolve pressure issues.
   Typical fix: Perform a complete transmission fluid flush using an exchange machine and the correct updated fluid (Mobil 1 Synthetic LV ATF HP or equivalent ACDelco fluid). A simple drain and fill is insufficient as it leaves contaminated fluid in the torque converter.
   Est. part cost: $200-$400 for a professional fluid exchange service.
3. Faulty Pressure Control Solenoid 'A' ⚪ Low Probability → Shop Transmission Valve Body While the solenoid can fail, transmission experts state it is rare for these specific solenoids to fail electrically or mechanically. The code is almost always a symptom of a hydraulic or mechanical problem elsewhere (valve body, pump, clutch pack) that affects the pressure in that solenoid's circuit.
   How to confirm: A technician can command the solenoid on and off with a high-end scan tool while monitoring pressure. The solenoid's resistance can also be tested, but this won't detect a mechanical sticking issue or a hydraulic leak affecting its operation.
   Typical fix: Replacement of the individual solenoid is not recommended. The solenoids are flow-rated and sold as part of the valve body assembly. Replacing a single one without proper programming can cause further issues.
   Est. part cost: $80-$150 for a single solenoid, but this is not the correct repair path.
4. Transmission Control Module (TCM) Software Issue ⚪ Low Probability → Shop Transmission Assembly TSB #N242480631-04 mentions this code appearing on vehicles that have already had a previous TCM software update, indicating a complex software/hardware interaction. [Bulletin #N242480631-04] Another TSB from late 2016 also pointed to a calibration anomaly causing P0747 that could be fixed with a software update.
   How to confirm: A Chevrolet dealership can check the vehicle's VIN for open recalls, special coverages, and available TCM software updates.
   Typical fix: Updating the TCM with the latest software calibration. This is often the first step a dealer will take.
   Est. part cost: $0-$200

Rare But Worth Checking

• Wiring Harness Damage: The internal transmission wiring harness is submerged in hot fluid and can become brittle. A short or open in the circuit for solenoid 'A' can trigger this code, though it's less common than hydraulic issues.
• Internal Mechanical Failure: In some GM transmissions, this code can be a symptom of a more severe internal problem like a failing torque converter or clutch pack, which sheds debris that contaminates the fluid and clogs the valve body. If the pan has excessive clutch material, a full rebuild is likely needed.

Diagnosis Steps

1. Check the transmission fluid level and condition. If it is low, dark, or smells burnt, this indicates a problem that may be more severe than just a solenoid.
2. Use a professional-grade scan tool to read the codes from the TCM and check for any related TSBs for the vehicle's VIN, especially TSB 18-NA-355 (shudder) and special coverage N242480631-04. [Bulletin #PIP5425A, 1, 4]
3. Check for available TCM software updates with a dealer or capable scan tool.
4. Monitor live transmission data, observing the commanded state vs. the actual state of Pressure Control Solenoid 'A' and related circuit pressures.
5. If shudder is present or fluid is old, perform a complete fluid exchange with Mobil 1 Synthetic LV ATF HP as per TSB 18-NA-355.
6. If the code persists, the next step is to remove the transmission pan to inspect for excessive metal or clutch debris. Significant debris points to a needed rebuild.
7. If the pan is clean, the valve body is the primary suspect. Test the electrical circuit for the solenoid to rule out a wiring issue.
8. Replace the entire valve body assembly. After installation, a 'Transmission Service Fast Learn' procedure must be performed using a scan tool to allow the TCM to learn the new components.

Parts You'll Likely Need

• Transmission Valve Body Assembly (OEM #24297344) — Wear in the valve body bores is the most common root cause of this code in the 8L90 transmission, causing pressure loss that the computer misinterprets as a stuck solenoid. The part comes with new solenoids which must be programmed.
  Trusted brands: ACDelco, GM Genuine Parts
  OEM price range: $800-$1500
  Aftermarket price range: $600-$1000
• Automatic Transmission Fluid (Mobil 1 Synthetic LV ATF HP) (OEM #ACDelco 10-4107 (GM #19417577)) — The original fluid is prone to moisture contamination, causing shudder and contributing to valve body issues. TSB 18-NA-355 specifies an upgrade to this new fluid via a full flush. A full flush requires 12+ quarts.
  Trusted brands: Mobil 1, ACDelco
  OEM price range: $15-$25 per quart
  Aftermarket price range: $12-$20 per quart
• Automatic Transmission Filter Kit (OEM #24274402) — A new filter and pan gasket are required any time the transmission pan is dropped for service, such as a valve body replacement.
  Trusted brands: ACDelco
  OEM price range: $40-$70
  Aftermarket price range: $25-$50

Related Codes That Often Appear With This One

• P0796 — TSB #PIP5425A explicitly states that P0747 (Pressure Control Solenoid 'A' Stuck On) and P0796 (Pressure Control Solenoid 'C' Stuck Off) may be found together, indicating a broader hydraulic control issue within the transmission. [Bulletin #PIP5425A, 15]
• P0700 — This is a generic code indicating that the Transmission Control Module (TCM) has stored a fault code. It will almost always be present alongside a specific transmission code like P0747.
• P0741 — This code for 'Torque Converter Clutch Circuit Performance or Stuck Off' is often seen on these transmissions and relates to the same family of hydraulic control issues, frequently caused by degraded fluid or valve body wear.

Technical Service Bulletins (TSBs) & Recalls

• N242480631-04: Notes gradual pressure loss causing harsh shifts and P0747 after a previous TCM update, extending coverage for a valve body repair.
• PIP5425A: Early TSB from 2016 acknowledging investigation into P0747 and P0796 codes on new 2017 models with 8-speed transmissions.
• 18-NA-355: Details the procedure for fixing a transmission shudder by flushing the old fluid and replacing it with Mobil 1 Synthetic LV ATF HP.
• PIE0383B: Mentions that P0747 can be caused by a calibration anomaly in the TCM on 2017 models, correctable with a software update.

Platform-Specific Known Issues

• TSB #N242480631-04 describes a special coverage for vehicles that set a P0747 after a previous TCM update, pointing to a known condition involving a gradual loss of pressure that causes harsh shifting. [Bulletin #N242480631-04]
• TSB #PIP5425A, issued early in the 6th gen Camaro's life cycle (Sept 2016), confirms that GM was aware of and investigating issues setting codes P0747 and P0796 on 2017 models with 8L45/8L90 transmissions. [Bulletin #PIP5425A, 15]
• TSB 18-NA-355 addresses a widespread 'shudder' issue on 8-speed transmissions caused by moisture-contaminated fluid. While not directly for P0747, performing the prescribed fluid flush with updated Mobil 1 LV ATF HP fluid is a critical first step and may prevent future valve body failure.