P066A Chevrolet Code - Cylinder 1 Glow Plug Control Circuit Low 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
- P066A Chevrolet indicates Cylinder 1 Glow Plug Control Circuit Low 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 P066A 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 P066A 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 P066A 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 P066A 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
- P066A 2014 Chevrolet Silverado — Cylinder 1 Glow Plug Control Circuit Low Voltage
- P066A 2015 Chevrolet Silverado — Cylinder 1 Glow Plug Control Circuit Low Voltage
- P066A 2016 Chevrolet Silverado — Cylinder 1 Glow Plug Control Circuit Low Voltage
- P066A 2017 Chevrolet Silverado — Cylinder 1 Glow Plug Control Circuit Low Voltage
- P066A 2018 Chevrolet Silverado — Cylinder 1 Glow Plug Control Circuit Low Voltage
Frequently Asked Questions about P066A Chevrolet Code
1. What does the OBDII code P066A mean on a Chevrolet?
P066A indicates a low voltage issue in the glow plug control circuit for cylinder 1, typically related to the glow plug system in diesel engines.
2. What are the common symptoms of code P066A?
Symptoms may include difficulty starting the engine, poor cold-weather performance, a check engine light, and reduced fuel efficiency.
3. What causes the P066A code to appear?
Common causes include a faulty glow plug, damaged wiring or connectors in the glow plug circuit, a malfunctioning glow plug control module, or corroded electrical connections.
4. Can I drive my Chevrolet with a P066A code?
While the vehicle may still run, driving with this code can lead to hard starts in cold weather and potential long-term damage to the engine if not addressed.
5. How do I diagnose the P066A code?
Start by inspecting the glow plug and its wiring for damage or corrosion. Use a multimeter to check for proper voltage and continuity in the circuit, and test the glow plug control module for proper operation.
6. How much does it cost to fix the P066A code on a Chevrolet?
Repair costs vary but typically range from $100 to $300, depending on whether the glow plug, wiring, or control module needs replacement.
7. Can a dead battery cause the P066A code?
A weak or dead battery can contribute to the code by providing insufficient voltage to the glow plug circuit, but this is less common than other causes.
8. How do I reset the P066A code after repairs?
After fixing the issue, use an OBDII scanner to clear the code. If the problem is resolved, the code should not return.
9. What happens if I ignore the P066A code?
Ignoring this code may lead to hard engine starts, reduced engine performance, and increased wear on the engine during cold weather operation.
10. Can a faulty glow plug control module trigger the P066A code?
Yes, a malfunctioning glow plug control module can fail to deliver the necessary voltage to the glow plug, causing the code to appear.
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