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 a problem with the glow plug circuit in the exhaust system, which is getting too much electricity.
The P26A2 code indicates that the voltage in the exhaust aftertreatment glow plug circuit is higher than expected by the vehicle's engine control module (ECM).
The exhaust aftertreatment system uses glow plugs to help reduce emissions by heating up the exhaust gases. The ECM monitors the voltage in the glow plug circuit to ensure it's operating correctly. If the voltage is too high, it triggers the P26A2 code.
• Check engine light is on
• Poor engine performance
• Increased emissions
• Faulty glow plug
• Wiring issues such as a short circuit
• Defective control module
Glow Plug: A device used to heat the air in the combustion chamber to help start diesel engines.
ECM: Engine Control Module, the computer that controls engine functions.
• Use an OBD-II scanner to confirm the code
• Inspect the glow plug and related wiring for damage
• Test the voltage in the glow plug circuit
• Replace the faulty glow plug
• Repair or replace damaged wiring
• Replace the control module if necessary
• OBD-II scanner
• Multimeter
• Socket set
$150 - $500
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram 2500
• Regularly inspect exhaust components
• Ensure proper maintenance of the electrical system
• Use high-quality fuel to reduce emissions
Sensor Issue
• Do not ignore the check engine light
• Consult a professional mechanic for accurate diagnosis
• Keep up with regular vehicle maintenance
Check with your vehicle manufacturer for specific warranty coverage on emissions-related components.
This code has become more common with the implementation of stricter emissions standards requiring more complex aftertreatment systems.
Moderate – While the vehicle may still function, emissions and performance can be affected.
Driving with a malfunctioning emissions system may not comply with local emissions laws and could lead to fines or penalties.
• Engine running
• Vehicle at operating temperature
The glow plug is typically located in the exhaust system, near the aftertreatment components such as the catalytic converter or DPF.
Q: Can I drive with a P26A2 code?
A: While the car may still run, it's not advisable to drive for long periods as it can lead to increased emissions and potential damage.
Q: How can I prevent this code from appearing?
A: Regular maintenance and inspection of the exhaust system and electrical components can help prevent this issue.
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Fitment Required · Vehicle-fitment part
Relevant when catalyst-efficiency or emissions faults persist after proper diagnosis.
Catalyst-efficiency faults sometimes point toward converter problems after proper testing.
Catalytic converters are highly vehicle-specific and should not be purchased by code alone.
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.