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 has detected that the voltage going to a part that helps sense the engine's performance is too high.
The Ion Sense Module is responsible for detecting ionization in the combustion chamber, which helps in monitoring the engine's performance. A high supply voltage indicates an issue with the electrical supply to this module.
The Ion Sense Module is used to detect ionization currents in the combustion chamber, which helps in optimizing the ignition timing and detecting misfires. The code P28C2 is triggered when the supply voltage to this module exceeds the manufacturer's specified range, indicating a potential fault in the power supply circuit or the module itself.
• Check Engine Light is on
• Poor engine performance
• Increased fuel consumption
• Faulty Ion Sense Module
• Wiring issues such as shorts or open circuits
• Faulty power supply or voltage regulator
Ion Sense Module: A device that detects ionization in the combustion chamber to monitor engine performance.
Voltage Regulator: A device that maintains a constant voltage level to electrical components.
• Check the battery voltage and charging system
• Inspect the wiring and connectors to the Ion Sense Module
• Test the Ion Sense Module for proper operation
• Repair or replace damaged wiring or connectors
• Replace the Ion Sense Module if faulty
• Ensure the voltage regulator is functioning correctly
• Multimeter
• OBD-II scanner
• Basic hand tools
$150 - $500
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regular maintenance of the vehicle's electrical system
• Ensure battery and alternator are in good condition
• Check and replace damaged wiring as needed
Sensor Issue
• Do not ignore the Check Engine Light
• Consult a professional mechanic if unsure
• Regularly check the vehicle's electrical connections
Check with the vehicle manufacturer for specific warranty coverage related to the Ion Sense Module.
This code is relatively uncommon and typically associated with vehicles using advanced ignition systems.
Moderate – Addressing this issue promptly can prevent further engine performance problems.
Driving with a malfunctioning Ion Sense Module can lead to increased emissions and reduced fuel efficiency.
• Engine running
• Use of a diagnostic tool to monitor voltage levels
The Ion Sense Module is typically located near the ignition coils or integrated within the engine control unit.
Q: Can I drive with code P28C2?
A: It's possible to drive short distances, but it's best to have it checked soon to avoid potential engine issues.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to poor engine performance and increased fuel consumption.
High-End · Full-system diagnostics
A full-system bidirectional platform aimed at advanced DIY users and professional diagnostic workflows.
Network faults often require full-system access instead of a generic code reader alone.
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Universal · Digital multimeter
A solid entry-level multimeter for voltage, continuity, resistance, and basic electrical troubleshooting.
Helpful for checking voltage drops, grounds, and basic circuit health when modules are not communicating.
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Universal · Wire connectors and repair kit
Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
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Fitment Required · Vehicle-fitment part
Commonly relevant for misfire, ignition-efficiency, and some drivability-related repairs.
Misfire and ignition-related faults commonly involve spark plugs as part of the repair path.
Check the correct plug type, gap, and engine application for your vehicle.
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Fitment Required · Vehicle-fitment part
Relevant when the fault points toward ignition-coil performance or cylinder-specific ignition issues.
Some ignition faults involve coil performance or cylinder-specific coil problems.
Match the coil to your engine and confirm the failed component before ordering.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.