P2718 on 2018-2019 Chevrolet Camaro: Pressure Control Solenoid 'D' Circuit Causes and Fixes

What's Unique About the 2018-2019 Chevrolet CAMARO

For the 2018-2019 Camaro with the 8L45 or 8L90 automatic transmission, this code has a very specific and documented cause. General Motors issued Service Update N182193520 acknowledging that on a number of vehicles, the electrical connectors for the valve body solenoids may not have been fully seated during factory assembly. This manufacturing issue, rather than a part failure, is the most probable reason for seeing a P2718 code on this particular car and its platform mates. The bulletin explicitly states the correction is to access the valve body and fully seat the two connectors, not to replace parts.

Diagnostic Flowchart

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

Symptoms You May Notice

• Check Engine Light is on
• Transmission enters 'limp home' mode with limited forward gears.
• Harsh, erratic, or delayed shifting, sometimes feeling like being hit from behind.
• Transmission slipping between gears.
• Vehicle may stall when coming to a stop.
• Increased fuel consumption.
• Vehicle may feel like it has a loss of power or is hesitating.

Most Likely Causes

1. Unseated Internal Transmission Solenoid Connector 🔴 High Probability → Shop Transmission Assembly This is a known manufacturing defect documented by General Motors in Technical Service Bulletin #N182193520 for this specific vehicle, transmission, and model years.
   How to confirm: A technician must remove the transmission pan and visually inspect the two valve body solenoid connectors, pressing firmly on them to ensure they are fully seated and click into place.
   Typical fix: Reseat the loose electrical connector(s). This also requires replacing the transmission fluid with the correct type (Mobil 1 Synthetic LV ATF HP) and replacing the transmission pan gasket.
   Est. part cost: $80-$170 (for fluid and gasket)
2. Low or Contaminated Transmission Fluid 🟡 Medium Probability → Shop Transmission Assembly The 8L transmissions are known to be sensitive to fluid type and condition. An incorrect fluid (like standard Dexron-VI instead of the required HP fluid) can cause shudder and other issues that may lead to codes.
   How to confirm: Check the transmission fluid level and condition via the specific procedure for this transmission 🎬 Watch: Step-by-step guide to servicing the 8-speed transmission fluid. (it has no dipstick). Fluid should be at the correct level, red in color, and not smell burnt.
   Typical fix: Perform a complete fluid flush with the correct Mobil 1 Synthetic LV ATF HP fluid and replace the filter.
   Est. part cost: $100-$200
3. Failed Pressure Control Solenoid 'D' ⚪ Low Probability → Shop Transmission Clutch Pressure Control Solenoid
   How to confirm: If the connector is properly seated, a technician can test the solenoid's internal resistance with a multimeter to see if it matches specifications. An open circuit (infinite resistance) within the solenoid itself indicates failure.
   Typical fix: Replace the faulty pressure control solenoid. This is done with the transmission pan removed. Solenoids must be replaced with the correct part number as they have different flow rates and characterization data.
   Est. part cost: $60-$100
4. Damaged Wiring or Connectors ⚪ Low Probability
   How to confirm: Visually inspect the external transmission wiring harness for any signs of damage, melting, or corrosion at the main connector. 🎬 Watch: How to replace a damaged internal transmission wiring harness. On Camaros, wiring harnesses near hot exhaust components can sometimes get damaged if not properly secured.
   Typical fix: Repair or replace the damaged section of the wiring harness.
   Est. part cost: $20-$300

Rare But Worth Checking

• Faulty Transmission Control Module (TCM): → Shop Transmission Assembly This is a rare cause and should only be considered after all other possibilities, including wiring and solenoids, have been thoroughly ruled out. The TCM is located inside the transmission on the valve body.

Diagnosis Steps

1. Check for Technical Service Bulletins (TSBs) related to the vehicle and code. For this Camaro, TSB #N182193520 is the most critical starting point.
2. Verify the transmission fluid level and condition using the manufacturer's specified procedure. Ensure the correct fluid type is being used.
3. Inspect the external transmission wiring harness and connectors for any visible damage, corrosion, or loose connections.
4. If external checks are inconclusive, follow the TSB procedure: safely raise the vehicle, drain the transmission fluid, and remove the transmission pan.
5. Locate the two valve body solenoid connectors (they are towards the front of the vehicle) and press firmly on each to ensure they are fully seated. A 'click' should be felt or heard.
6. If connectors are already seated, test the resistance of Pressure Control Solenoid 'D' with a multimeter to check for an internal open circuit. 🎬 See this deep dive into 8L90 electrical theory and operation. The resistance should be between 4.5 and 5.5 ohms.
7. If the solenoid tests good, check for continuity on the wiring harness between the TCM and the solenoid connector.
8. If all wiring and components test good, the issue may lie with the Transmission Control Module (TCM) itself, which is part of the valve body assembly.

Parts You'll Likely Need

• Automatic Transmission Fluid (OEM #19418393 (ACDelco Gold / Mobil 1 Synthetic LV ATF HP)) — The transmission fluid must be drained to access the internal connectors and must be replaced with this specific type. Using the wrong fluid can cause damage.
  Trusted brands: ACDelco, Mobil 1
  OEM price range: $15-$25 per quart
  Aftermarket price range: $12-$20 per quart
• Automatic Transmission Fluid Pan Gasket (OEM #24260071) — The gasket should be replaced whenever the transmission pan is removed to prevent leaks.
  Trusted brands: ACDelco, Fel-Pro
  OEM price range: $30-$50
  Aftermarket price range: $20-$35
• Pressure Control Solenoid 'D' (S5) (OEM #24272282) — This part is only needed if the solenoid itself has failed, which is less likely than the loose connector issue on this vehicle. This solenoid is a 'Normally High' type.
  Trusted brands: ACDelco (GM Genuine)
  OEM price range: $60-$100
  Aftermarket price range: $40-$80

Related Codes That Often Appear With This One

• P2720 — This code ('Pressure Control Solenoid 'D' Control Circuit Low') is mentioned in the same Technical Service Bulletin (N182193520) as P2718 and can be caused by the exact same unseated connector issue.

Technical Service Bulletins (TSBs) & Recalls

• N182193520: States that on a small number of vehicles (including 2018-2019 Camaro, 2019 Corvette, Colorado/Canyon, Silverado/Sierra), the electrical connector to the transmission valve body solenoids may not be fully seated. This can result in DTC P2718 or P2720, causing the transmission to enter a 'limp home' mode. The correction is to access the valve body and firmly press on the two connectors to ensure they are seated.

Platform-Specific Known Issues

• Known Manufacturing Defect (TSB N182193520): TSB N182193520 documents a known manufacturing issue where the electrical connectors for the transmission valve body solenoids may not be fully seated, directly causing codes P2718 or P2720. The fix is to reseat the connectors, not replace parts.
• Owner Repair Experience: A user on Camaro6.com with a 2018 Camaro SS reported their car suddenly went into limp mode with a Check Engine Light. The dealer diagnosed code P2718 and performed the fix outlined in TSB N182193520. The repair, which involved dropping the pan and reseating the connector, was covered under warranty and resolved the issue completely.

Mechanic-Grade Diagnostic Values

• Pressure Control Solenoid Resistance — expected: 4.5–5.5 ohms. Failure: A reading of infinite resistance (OL) indicates an open circuit and a failed solenoid. A reading outside the specified range also indicates a problem.

Scan Tool Commands That Help

• GDS2 (Global Diagnostic System 2): Solenoid Characterization Programming — This function is required after replacing a solenoid, the valve body, or the TCM. It downloads the unique performance data (PUN/TUN) for the new part to the TCM to ensure proper operation and shift quality.
• GDS2 (Global Diagnostic System 2): Transmission Service Fast Learn — After any internal transmission repair, valve body replacement, or TCM programming, this procedure must be run. It allows the TCM to perform a series of tests to learn the individual clutch apply pressures, which is critical for proper shift timing.
• GDS2 (Global Diagnostic System 2): Output Control Functions — A technician can use this to command individual solenoids on and off to verify electrical circuit integrity and basic solenoid function without having to remove the transmission pan, assuming the circuit is not already open.

Wiring & Ground Locations

• Internal Valve Body Connectors — Inside the transmission, on the valve body. Accessible after removing the transmission pan and filter. The TSB specifically refers to two connectors that may be unseated.. This is the most likely point of failure for this code on this vehicle, due to the known manufacturing defect described in TSB N182193520.
• Main Transmission Harness Connector (X185) — The external 16-pin electrical connector on the outside of the transmission case where the main vehicle harness connects to the transmission's internal harness and TCM.. This is the primary point for testing the wiring harness from outside the transmission. A fault here could cause this code, though it is less likely than the internal connector issue.
• BCM Ground — While not specific to the transmission, general vehicle grounds are critical. On the Camaro platform, the Body Control Module (BCM) is located under the driver's side dash, and ensuring its ground connections are clean and tight can prevent various electrical issues.. A poor ground can cause unpredictable behavior in electronic modules, although it is not a primary suspect for a specific circuit code like P2718.

OEM Part Supersession History

• 24272282 → 24044716 — Unknown/Not specified. This information comes from third-party parts sellers.
  Heads up: According to third-party sellers, 24044716 is the replacement for 24272282. However, always verify the latest part number with a GM dealer. Part number 24272282 is used for multiple 'Normally High' solenoids (S1, S5, and S6), so it is critical to install it in the correct valve body location for Solenoid 'D' (S5).