Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This means that the car's computer is having trouble with one of its power supplies. It's like if your tablet was having trouble charging because the power cable wasn't working right.
The code indicates an issue with the voltage supply to one of the internal control modules in the vehicle, specifically voltage supply 3. This can affect the module's performance.
The P16E9 code is triggered when the Engine Control Module (ECM) detects a performance issue with the voltage supply circuit 3. The ECM monitors the voltage levels to ensure they are within specified parameters. If the voltage is too high or too low, the ECM will log this code.
• Check Engine Light is on
• Vehicle may not start
• Electrical components may not function properly
• Faulty wiring or connectors in the voltage supply circuit
• Defective control module
• Battery or alternator issues
ECM: Engine Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use a scan tool to verify the code and check for other related codes.
• Inspect the wiring and connectors for damage or corrosion.
• Test the battery and alternator to ensure proper voltage output.
• Repair or replace damaged wiring or connectors.
• Replace the faulty control module if necessary.
• Ensure the battery and alternator are functioning correctly.
• OBD-II scan tool
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Chevrolet Malibu
• Buick Regal
• GMC Sierra
• Regularly check battery and alternator health.
• Inspect wiring for wear and tear.
• Perform regular vehicle diagnostics.
Electrical Issue
• Have your vehicle inspected by a professional mechanic.
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
Check with your vehicle manufacturer for warranty coverage on control modules and electrical systems.
This code has been associated with vehicles experiencing electrical issues due to aging components or poor maintenance.
Moderate – It is recommended to address this issue soon to avoid potential vehicle starting problems.
Driving with electrical issues can lead to unexpected vehicle shutdowns, which may be unsafe.
• Vehicle must be running.
• Electrical systems should be under normal load conditions.
The control module is typically located in the engine bay or under the dashboard, depending on the vehicle model.
Q: Can I drive with a P16E9 code?
A: It's not recommended to drive with this code, as it may lead to further electrical issues or vehicle shutdowns.
Q: How can I prevent this code from appearing?
A: Regular maintenance of the vehicle's electrical system and components can help prevent this code.
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