Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means something inside the car's computer isn't working right. It's like when a computer has a glitch and doesn't do what it's supposed to do.
The code P16D3 indicates that there is an internal issue with the Engine Control Module (ECM) or Powertrain Control Module (PCM).
P16D3 is a diagnostic trouble code (DTC) that indicates a performance issue within the ECM/PCM. This might involve a malfunction in the internal circuitry or processing capabilities of the module, affecting its ability to manage the engine or powertrain functions effectively.
• Check Engine Light is on
• Poor engine performance
• Engine stalling or misfiring
• Reduced fuel efficiency
• Faulty ECM/PCM
• Software issue within the ECM/PCM
• Electrical short or open circuit in the ECM/PCM
• Corrosion or damage to ECM/PCM connectors
ECM: Engine Control Module
PCM: Powertrain Control Module
DTC: Diagnostic Trouble Code
• Use an OBD-II scanner to confirm the code.
• Inspect the ECM/PCM connectors for corrosion or damage.
• Check for any software updates or recalls for the ECM/PCM.
• Test the electrical circuits related to the ECM/PCM.
• Replace the ECM/PCM if found faulty.
• Reprogram or update the ECM/PCM software.
• Repair or replace damaged connectors or wiring.
• Clear the code and test drive to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Screwdriver set
$500 - $1500
Difficult
• Chevrolet Malibu
• Buick LaCrosse
• Cadillac ATS
• Regularly update ECM/PCM software.
• Avoid exposing the ECM/PCM to moisture.
• Perform regular maintenance checks.
Engine Performance
• Consult a professional mechanic for diagnosis.
• Do not ignore the Check Engine Light.
• Avoid driving if the vehicle is stalling frequently.
Check if the vehicle's powertrain warranty covers ECM/PCM issues.
This code has been associated with internal ECM/PCM failures in certain vehicle models, often requiring module replacement.
High – This issue can affect the drivability and safety of the vehicle.
Driving with a malfunctioning ECM/PCM can lead to unsafe driving conditions. It is advisable to address this issue promptly.
• Engine running
• Vehicle in park or neutral
The ECM/PCM is typically located in the engine bay or under the dashboard, depending on the vehicle model.
Q: Can I drive with a P16D3 code?
A: It's not recommended to drive with this code as it may lead to further engine or powertrain issues.
Q: Will resetting the ECM/PCM fix the P16D3 code?
A: Resetting might clear the code temporarily, but if the underlying issue is not resolved, the code will likely return.
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