P066C Chevrolet Code - Cylinder 2 Glow Plug Control Circuit Low Voltage
Quick Answer
n the diesel engine, air alone is compressed in the cylinder. Common causes include Faulty cylinder #2 glow plug, Cylinder #2 glow plug harness is open or shorted, Cylinder #2 glow plug circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P066C Chevrolet indicates Cylinder 2 Glow Plug Control Circuit Low Voltage.
- Common causes
- Common causes include Faulty cylinder #2 glow plug, Cylinder #2 glow plug harness is open or shorted, Cylinder #2 glow plug circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P066C Chevrolet Description
Control of the glow plugs is accomplished by the Glow Plug Control Module. The nominal voltage for the glow plugs is 5.4 volts. When the ignition is turned On, the Glow Plug Control Module applies 7.2 V for 2.2 s, then 5.7 V for 0.8 s, and then 5.4 V until 1200°C (2192°F) is reached. The maximum voltage of the system is 10 V. While the engine is running the voltage will vary between 4.7 - 10 V when in closed loop control to maintain a glow plug temperature that ranges from 1150° - 1180°C (2102° - 2156°F). The temperature and the power consumption are controlled between the Engine Control Module (ECM) and the Glow Plug Control Module within a wide range to suit the engine's pre-heating requirements. Each glow plug is energized individually. This capability yields more optimum heat times for the glow plugs, thus pre - glow times can be kept to a minimum for a short wait to crank times and maximum glow plug durability.
What are the Possible Causes of the DTC P066C Chevrolet?
- Faulty cylinder #2 glow plug
- Cylinder #2 glow plug harness is open or shorted
- Cylinder #2 glow plug circuit poor electrical connection
- Faulty Glow Plug Control Module
How to Fix the DTC P066C Chevrolet?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P066C Chevrolet code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Information for Specific Chevrolet Models
- P066C 2014 Chevrolet Silverado — Cylinder 2 Glow Plug Control Circuit Low Voltage
- P066C 2015 Chevrolet Silverado — Cylinder 2 Glow Plug Control Circuit Low Voltage
- P066C 2016 Chevrolet Silverado — Cylinder 2 Glow Plug Control Circuit Low Voltage
- P066C 2017 Chevrolet Silverado — Cylinder 2 Glow Plug Control Circuit Low Voltage
- P066C 2018 Chevrolet Silverado — Cylinder 2 Glow Plug Control Circuit Low Voltage
Frequently Asked Questions about P066C Chevrolet Code
What does the OBDII code P066C mean for a Chevrolet?
P066C indicates that the Cylinder 2 Glow Plug Control Circuit is experiencing low voltage, which affects the glow plug's ability to heat properly for diesel engine starting.
What are the common symptoms of code P066C?
Symptoms include difficulty starting the engine, rough idling, increased exhaust smoke during startup, and reduced engine performance in cold weather.
What causes code P066C on a Chevrolet?
Common causes include a faulty glow plug, damaged wiring or connectors in the glow plug circuit, a malfunctioning glow plug control module, or corrosion in the electrical connections.
How can I diagnose code P066C?
Start by inspecting the glow plug, wiring, and connectors for damage or corrosion. Use a multimeter to check for proper voltage in the glow plug circuit and scan for related codes to pinpoint the issue.
Can I drive my Chevrolet with code P066C?
You can drive the vehicle, but it may struggle to start, especially in cold weather. Prolonged driving with this issue could lead to further damage or reduced engine performance.
How do I fix code P066C on a Chevrolet?
Repairs may include replacing the faulty glow plug, repairing damaged wiring or connectors, cleaning corroded connections, or replacing the glow plug control module if necessary.
How much does it cost to repair code P066C?
The repair cost can vary depending on the specific issue. Glow plug replacement typically costs $100-$300, while control module repairs may range from $300-$500, excluding labor.
Can a bad glow plug cause other engine problems?
Yes, a bad glow plug can lead to poor engine performance, increased emissions, and difficulty starting the vehicle in cold conditions.
How do I prevent code P066C from occurring?
Regular maintenance, including inspecting the glow plug system and addressing wiring issues promptly, can help prevent this code.
Can a failing glow plug control module trigger code P066C?
Yes, a malfunctioning glow plug control module can cause low voltage in the cylinder 2 glow plug circuit, leading to code P066C.
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