Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is planning to restart itself to fix a problem. It's like when your computer restarts to update or fix something.
The control module has detected a condition that requires a planned warm reset to ensure proper operation.
The P16D4 code indicates that the vehicle's control module has initiated a planned software reset. This is typically a self-preservation action to ensure the module continues to operate correctly. The reset is 'warm,' meaning it occurs while the system is still powered, as opposed to a 'cold' reset which occurs when the system is powered off.
• Check engine light is on
• Temporary loss of power
• Unusual vehicle behavior
• Software glitch
• Corrupted data in the control module
• Temporary communication error
Control Module: A computer in the vehicle that manages various functions.
Warm Reset: A restart of the system while it is still powered on.
• Check for any other related codes.
• Inspect the control module connections and wiring.
• Perform a software update or reflash if available.
• Clear the code and test drive to see if it returns.
• Update the control module software.
• Replace the control module if necessary.
• OBD-II scanner
• Multimeter
• Diagnostic software
$100 - $500
Moderate
• Chevrolet Malibu
• Buick Regal
• GMC Terrain
• Regular software updates
• Routine diagnostic checks
• Proper maintenance of electrical systems
Control Module Issue
• Have the vehicle checked by a professional.
• Avoid ignoring the check engine light.
• Keep your vehicle's software up to date.
Check with your vehicle manufacturer as control module issues may be covered under warranty.
This code has been reported in vehicles with software issues that were resolved with updates.
Moderate – It should be addressed soon to prevent potential drivability issues.
Ignoring this code could lead to vehicle performance issues and may affect emissions compliance.
• Vehicle at operating temperature
• Engine running
The control module is typically located under the dashboard or in the engine compartment.
Q: Can I drive with a P16D4 code?
A: It's possible to drive for a short period, but it's best to get the issue checked soon to avoid potential problems.
Q: Will a software update fix the P16D4 code?
A: In many cases, a software update can resolve the issue if it's due to a software glitch.
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