P066B Chevrolet Code - Cylinder 1 Glow Plug Control Circuit High Voltage
Quick Answer
n the diesel engine, air alone is compressed in the cylinder. Common causes include Faulty cylinder #1 glow plug, Cylinder #1 glow plug harness is open or shorted, Cylinder #1 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
- P066B Chevrolet indicates Cylinder 1 Glow Plug Control Circuit High Voltage.
- Common causes
- Common causes include Faulty cylinder #1 glow plug, Cylinder #1 glow plug harness is open or shorted, Cylinder #1 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 P066B 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 P066B Chevrolet?
- Faulty cylinder #1 glow plug
- Cylinder #1 glow plug harness is open or shorted
- Cylinder #1 glow plug circuit poor electrical connection
- Faulty Glow Plug Control Module
How to Fix the DTC P066B 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 P066B 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
- P066B 2014 Chevrolet Silverado — Cylinder 1 Glow Plug Control Circuit High Voltage
- P066B 2015 Chevrolet Silverado — Cylinder 1 Glow Plug Control Circuit High Voltage
- P066B 2016 Chevrolet Silverado — Cylinder 1 Glow Plug Control Circuit High Voltage
- P066B 2017 Chevrolet Silverado — Cylinder 1 Glow Plug Control Circuit High Voltage
- P066B 2018 Chevrolet Silverado — Cylinder 1 Glow Plug Control Circuit High Voltage
Frequently Asked Questions about P066B Chevrolet Code
What does the OBDII code P066B mean on a Chevrolet?
The P066B code indicates a high voltage issue in the Cylinder 1 Glow Plug Control Circuit, which helps heat the glow plug for proper engine starting in diesel vehicles.
What are the common symptoms of the P066B code?
Symptoms may include difficulty starting the engine, rough idling, reduced fuel efficiency, and an illuminated check engine light.
What causes the P066B code to appear?
Possible causes include a faulty glow plug, damaged glow plug control module, wiring issues (e.g., frayed wires or poor connections), or a malfunctioning ECU.
Can I drive my Chevrolet with the P066B code?
Driving with this code is not recommended, as it may lead to hard starting, increased emissions, or further damage to the glow plug system.
How do I diagnose the P066B code on my Chevrolet?
Diagnosis involves inspecting the glow plug, wiring, and connectors for damage, testing the glow plug control module, and using a multimeter to check circuit voltage.
How can I fix the P066B code?
Repairs may include replacing the faulty glow plug, repairing damaged wiring, cleaning or tightening connections, or replacing the glow plug control module.
What tools are needed to troubleshoot the P066B code?
You may need an OBDII scanner, a multimeter, wire repair tools, and possibly a replacement glow plug or control module.
Is the P066B code covered under warranty for my Chevrolet?
Warranty coverage depends on your vehicle’s age, mileage, and warranty terms. Consult your dealership or warranty provider for details.
How much does it cost to repair the P066B code?
Repair costs vary, ranging from $50–$150 for a new glow plug to $200–$500 if the glow plug control module needs replacement, plus labor charges.
Can a bad battery cause the P066B code?
Yes, a weak or failing battery can result in insufficient power to the glow plug circuit, potentially triggering the P066B code.
Discuss the causes and fixes for P066B Chevrolet OBDII Code
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