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 getting a signal that's too strong from the part that helps start the engine.
The P038C code indicates that the powertrain control module (PCM) has detected a high voltage condition in the ignition I control signal circuit.
The ignition I control signal circuit is responsible for managing the voltage sent to the ignition system to start the engine. A 'high' signal indicates that the voltage is above the expected range, which can cause issues with engine starting or performance.
• Engine misfire
• Difficulty starting the engine
• Check Engine Light illuminated
• Faulty ignition coil
• Wiring issues such as shorts or open circuits
• Faulty PCM
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Check for any stored codes and freeze frame data.
• Inspect the ignition coil and related wiring for damage.
• Test the voltage and ground signals at the ignition coil.
• Replace the faulty ignition coil.
• Repair or replace damaged wiring.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Chevrolet Silverado
• Ford F-150
• Toyota Camry
• Regular maintenance of ignition components.
• Check and replace spark plugs as needed.
• Inspect wiring for any signs of wear or damage.
Engine Performance
• Avoid driving the vehicle until the issue is resolved.
• Consult a professional mechanic for diagnosis and repair.
Check with your vehicle manufacturer for warranty coverage on ignition system components.
This code is relatively uncommon and typically associated with ignition system issues.
Moderate – While the vehicle may still be drivable, it can lead to more severe engine performance issues if not addressed.
Ignoring this code can lead to increased emissions and potential engine damage.
• Engine at operating temperature
• Vehicle in park or neutral
The ignition coil is typically located on top of the engine, near the spark plugs.
Q: Can I drive with a P038C code?
A: It's not recommended as it can lead to engine performance issues.
Q: How do I clear the P038C code?
A: The code can be cleared with an OBD-II scanner after repairs are made.
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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.