P0601 on 2015-2018 Chevrolet Silverado 1500: ECM/TCM Failure Causes & Fixes

What's Unique About the 2015-2018 Chevrolet SILVERADO 1500

For the 2015-2018 Silverado, this code is notable because General Motors has issued specific Technical Service Bulletins (TSBs) acknowledging that P0601 can be set by either the Engine Control Module (ECM) or the Transmission Control Module (TCM). TSB #PIP5609 specifically advises technicians to inspect the ECM's electrical connections and power/ground circuits before condemning the unit, suggesting that wiring and connection integrity are known concerns on this platform. TSB #PIP4653E confirms that the TCM is another common source of this code, making it crucial to identify which module is at fault before starting repairs.

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
• Service Stabilitrak message may appear
• Service Traction Control message may appear
🎬 Watch: How to reset the StabiliTrak message on your Chevy
• Vehicle enters 'Reduced Engine Power' or 'Limp Mode'
• Engine may crank but not start, or may not crank at all
• Intermittent stalling while driving
• Harsh or erratic transmission shifting
• Poor engine performance and fuel economy

Most Likely Causes

1. Internal Failure of the Engine Control Module (ECM) 🔴 High Probability Heat cycles, vibration, and age can cause the internal memory chips or processor of the ECM to fail. If the P0601 code returns immediately after being cleared and all external electrical inputs are verified as good, it almost always points to a fatal internal module fault.
   How to confirm: After verifying stable battery voltage (12.6V+ off, 13.5-14.5V running) and clean connections, use a professional scan tool to confirm the code originates in the ECM. If the code comes back instantly after clearing, the ECM is condemned. In some cases, pouring water on the ECM to cool it down may temporarily allow the vehicle to restart, further indicating an internal thermal failure.
   Typical fix: Replace the Engine Control Module. The new module must be programmed to the truck's VIN and security system using a GM-specific tool like SPS2. Some companies offer mail-in services to clone an existing module or provide pre-programmed replacements. 🎬 See how to clone or program a replacement Silverado PCM
   Est. part cost: $250-$700
2. Internal Failure of the Transmission Control Module (TCM) 🟡 Medium Probability As cited in GM TSB #PIP4653E, the TCM is another known source for P0601 on these trucks. The internal electronics are subject to the same failures as the ECM, leading to a checksum error within the transmission's dedicated controller.
   How to confirm: Use a professional scan tool (like a Tech 2 or GDS2) to verify that the P0601 code is stored in the TCM, not the ECM. The diagnostic procedure must be targeted at the module that is logging the fault.
   Typical fix: Replace the Transmission Control Module. Like the ECM, a new TCM requires professional programming to the vehicle.
   Est. part cost: $170-$450
3. Poor Electrical Connections or Low Voltage 🟡 Medium Probability GM TSB #PIP5609 explicitly directs technicians to check the ECM's electrical connections and power supply. A documented repair on a 2011 Silverado with P0601 showed the cause to be broken ground wires near the driver's side motor mount, behind the power steering pump. 🎬 Watch: How broken ground wires can mimic a module failure These ground points are susceptible to vibration and corrosion, which can cause voltage drops or spikes that corrupt the module's memory or mimic an internal fault.
   How to confirm: Load test the battery and test the alternator output (should be 13.5-14.5V when running). Disconnect, inspect, and clean the ECM/TCM connectors and ground points. Specifically check ground G101 at the lower front of the engine block and other grounds on the cylinder heads and frame. A voltage drop test across ground straps should show less than 0.2 volts.
   Typical fix: Clean and tighten all relevant ground straps and module connectors. Repair any broken or corroded wires. A common repair involves extending and relocating the problematic ground near the motor mount to a more secure location on the engine block. Apply dielectric grease to protect the connection. Replace the battery or alternator if they fail testing.
   Est. part cost: $0-$400

Rare But Worth Checking

• Failed Aftermarket Programming: If the vehicle has been tuned with an aftermarket performance calibration, a failed or improper 'flash' can corrupt the module's memory and set a P0601 code. One owner reported the code only appeared when his performance tune was loaded and disappeared when flashed back to stock.

Diagnosis Steps

1. Connect a professional OBD-II scanner and determine which module is setting the P0601 code (ECM or TCM). Note any other codes present.
2. Perform a full vehicle electrical system check. Load test the battery and verify the alternator is charging correctly (typically 13.5-14.5 volts with the engine running).
3. Following the guidance of TSB #PIP5609, inspect the main power and ground wires leading to the module. Check for any chafing, breaks, or loose connections.
4. Specifically locate and inspect the ground wires on a stud near the driver's side motor mount, behind the power steering pump, as this is a documented failure point.
5. Inspect other key grounds, such as G101 at the lower front of the engine block and straps from the engine to the firewall/chassis.
6. Disconnect the battery. Then, disconnect the electrical connectors from the identified faulty module (ECM or TCM). Inspect the connector pins and the module's pins for any signs of corrosion, moisture, or damage. Clean with electrical contact cleaner if necessary.
7. Reconnect everything securely. Clear the codes and start the vehicle. If the P0601 code returns immediately, the control module has an internal hardware failure and must be replaced.
8. If the code does not return immediately, the issue was likely related to a poor connection or transient low voltage.

Parts You'll Likely Need

• Engine Control Module (ECM) (OEM #12673676) — This is the most common cause of a persistent P0601 code when it originates from the engine controller. The internal memory fails, requiring replacement.
  Trusted brands: ACDelco
  OEM price range: $400-$700
  Aftermarket price range: $250-$500
• Transmission Control Module (TCM) (OEM #24279973) — If the scan tool identifies the TCM as the source of the P0601 code, this module has failed and needs to be replaced.
  Trusted brands: ACDelco
  OEM price range: $170-$300
  Aftermarket price range: $150-$250

Related Codes That Often Appear With This One

• P0603 — This code indicates a Keep Alive Memory (KAM) error, which is closely related to the main checksum error.
• P0604 — This code indicates a Random Access Memory (RAM) error, another type of internal module memory fault.
• P0606 — This code indicates a general PCM/ECM Processor Fault, pointing to a severe internal failure.
• P062F — This code relates to an internal EEPROM error and is specifically mentioned alongside P0601 in GM TSBs for both the ECM and TCM. [Bulletin #PIP5609, #PIP4653E]

Technical Service Bulletins (TSBs) & Recalls

• PIP5609: Advises checking ECM electrical connections for P0601 and other codes.
• PIP4653E: Notes that P0601 can be stored in the Transmission Control Module (TCM).

Platform-Specific Known Issues

• TSB #PIP5609: This bulletin applies to 2016-2018 models and advises checking all ECM power and ground supply circuits for connection/terminal tension issues before replacing the module for a P0601 code.
• TSB #PIP4653E: This bulletin covers 2015 models (among others) and highlights that DTCs P0601, P0603, P0604, P062F, or P1621 can be stored in the Transmission Control Module (TCM), requiring diagnosis to focus on the TCM if identified as the source.
• Real-World Ground Failure: A widely documented repair for P0601 with stalling and 'Reduced Power' messages on a similar GM truck involved no module replacement. The fix was repairing two broken ground wires on a stud behind the power steering pump near the driver's side motor mount. This highlights that external wiring, especially grounds, is a critical failure point before condemning a module.