P2066 Chevrolet Code - Fuel Level Sensor 2 Performance
Quick Answer
Diesel Engine The primary fuel level sensor and the secondary fuel level sensor change resistance based on fuel level. Common causes include Faulty Fuel Level Sensor, Fuel Level Sensor harness is open or shorted, Fuel Level Sensor 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
- P2066 Chevrolet indicates Fuel Level Sensor 2 Performance.
- Common causes
- Common causes include Faulty Fuel Level Sensor, Fuel Level Sensor harness is open or shorted, Fuel Level Sensor 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 P2066 Chevrolet Description
The primary fuel level sensor and the secondary fuel level sensor change resistance based on fuel level. The Fuel Pump Driver Control Module monitors the signal circuits of the primary fuel level sensor and the secondary fuel level sensor and sends the signal information to the Engine Control Module (ECM) for all further handling. The ECM uses this value in order to determine the fuel level. When the fuel tank is full, the resistances of both fuel level sensors are low, and the ECM senses a low signal voltage on both the signal circuits of the primary fuel level sensor and the secondary fuel level sensor. When the fuel tank is empty, the resistances of the fuel level sensors are high, and the ECM senses a high signal voltage. The ECM uses the signal circuits of the primary fuel level sensor and the secondary fuel level sensor in order to calculate the percentage of remaining fuel in the tank. The ECM sends the fuel level percentage via the serial data circuit to the instrument cluster in order to control the fuel gauge.
Gasoline Engine
The primary fuel level sensor and the secondary fuel level sensor change resistance based on fuel level. The Engine Control Module (ECM) monitors the signal circuits of the primary fuel level sensor and the secondary fuel level sensor in order to determine the fuel level. When the fuel tank is full, the resistances of both fuel level sensors are low, and the ECM senses a low signal voltage on both the signal circuits of the primary fuel level sensor and the secondary fuel level sensor. When the fuel tank is empty, the resistances of the fuel level sensors are high, and the ECM senses a high signal voltage. The ECM uses the signal circuits of the primary fuel level sensor and the secondary fuel level sensor in order to calculate the percentage of remaining fuel in the tank. The ECM sends the fuel level percentage via the serial data circuit to the instrument cluster in order to control the fuel gauge.
The Diagnostic Trouble Code (DTC) will be set if the ECM detects a change in fuel level of less than a specified amount (typically 3 - 10 L or 0.8 - 2.6 gal) over a specified driving distance (typically 240 - 320 km or 150 - 200 miles).
What are the Possible Causes of the DTC P2066 Chevrolet?
- Faulty Fuel Level Sensor
- Fuel Level Sensor harness is open or shorted
- Fuel Level Sensor circuit poor electrical connection
- Faulty Instrument Cluster
- Faulty Engine Control Module (ECM)
How to Fix the DTC P2066 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.
Code Tech Notes
There is a factory service bulletin for the following Chevrolet models:
2007 Chevrolet Silverado 3500 Chassis Cab
2008 Chevrolet Silverado 3500 Chassis Cab
2009 Chevrolet Silverado 3500 Chassis Cab
2007-2009 Chevrolet Silverado 3500 Chassis Cab Factory Service Bulletin ODBII Code P2066
Models: 2007-2008 Chevrolet Corvette
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Some customers may comment that the Fuel gauge goes to empty when the fuel level is greater than what is shown on the gauge and DTCs P2066 and P2636 are present. When these codes are present the Fuel Level Low message should be displayed on the DIC. This could be caused if the ECM does not receive the expected voltage signal to indicate that the fuel transfer is properly occurring. If this condition exists for 30 minutes both of these DTCs will be set. The fuel level sensor card may have slight discoloration possibly caused by fuel contamination which can affect the level of sensor output. The fuel level sensor diagnostics are sensitive to this issue.
Recommendation/Instructions:
Verify that P2066 and P2636 DTC are set.
Confirm fuel rail pressure with the fuel pump on is 58-62 psi. If the pressure is not within this range, follow eSI Service Procedures.
Confirm proper jet pump transfer by checking and recording the fuel level sensor voltages using a Tech2. This must be performed with less than 3/4 tank of fuel. If required, remove sufficient fuel from the Schrader valve on the fuel rail. Follow all safety procedures as outlined in SI. Clear the DTCs to get a reading on the fuel gauge. If the secondary (passenger side) sender is less than 2.2 volts and the primary (driver side) is more than .86 volts, the secondary (passenger side) level sensor and the module (includes the jet pump) should be replaced. Prior to replacing fuel hardware confirm all wiring connections are fully seated and harnesses are properly routed.
If the jet transfer pump is operating properly the fuel sender card may be contaminated. This could cause an incorrect voltage signal to be sent to the ECM. Customers should be advised to correct a contamination issue by adding one bottle of GM Fuel System Treatment PLUS (part number 88861011) to the fuel system on their next fuel fill. Note; the fuel level must be below ¼ tank when the fuel treatment is added. The treatment rate is 1 oz. per gallon of fuel (Using one 20 oz bottle to the fuel system is acceptable). To clean a severely contaminated fuel level sensor, it is permissible to treat the fuel system on two consecutive tanks.
Note: Back to back treatment is only permitted once in the life of the vehicle. After the initial treatment, customers should be advised to add one bottle of GM Fuel System Treatment PLUS to the fuel tank at every oil change, however, not more frequently than once every 3000 miles.
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What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P2066 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
- P2066 2014 Chevrolet Silverado — Fuel Level Sensor 2 Performance
- P2066 2015 Chevrolet Silverado — Fuel Level Sensor 2 Performance
- P2066 2016 Chevrolet Silverado — Fuel Level Sensor 2 Performance
- P2066 2017 Chevrolet Silverado — Fuel Level Sensor 2 Performance
- P2066 2018 Chevrolet Silverado — Fuel Level Sensor 2 Performance
Frequently Asked Questions about P2066 Chevrolet Code
1. What are the common symptoms of OBDII code P2066 on a Chevrolet related to Fuel Level Sensor 2 Performance?
The common symptoms of P2066 may include inaccurate fuel gauge readings, fluctuating fuel level readings, or a fuel gauge that constantly shows empty or full.
2. What are the possible causes of OBDII code P2066 Fuel Level Sensor 2 Performance on a Chevrolet?
Possible causes of P2066 can include a faulty fuel level sensor, damaged wiring or connectors to the sensor, a defective fuel pump module, or issues with the vehicle's powertrain control module (PCM).
3. How can I diagnose the OBDII code P2066 on my Chevrolet related to Fuel Level Sensor 2 Performance?
Diagnosing P2066 typically involves checking the fuel level sensor for proper operation, inspecting wiring and connectors for damage, testing the fuel pump module, and scanning the PCM for any related fault codes.
4. Can a DIY enthusiast repair OBDII code P2066 Fuel Level Sensor 2 Performance on a Chevrolet?
While diagnosing and repairing P2066 may require some technical knowledge and tools, DIY enthusiasts can attempt to replace a faulty fuel level sensor or repair damaged wiring if they have the necessary skills and resources.
5. Is it safe to drive my Chevrolet with OBDII code P2066 Fuel Level Sensor 2 Performance?
It is generally safe to drive with P2066, but you may experience inaccurate fuel level readings, which can lead to running out of fuel unexpectedly. It is recommended to address the issue promptly to avoid potential inconvenience.
6. How much does it typically cost to repair OBDII code P2066 on a Chevrolet related to Fuel Level Sensor 2 Performance?
The cost of repairing P2066 can vary depending on the cause of the issue and labor rates in your area. Replacing a fuel level sensor or repairing wiring may cost a few hundred dollars, while addressing more complex issues could cost more.
7. Can a bad fuel level sensor cause other problems in a Chevrolet besides triggering OBDII code P2066?
Yes, a malfunctioning fuel level sensor can cause other issues such as incorrect fuel level readings, fuel gauge inaccuracies, and potentially affect the vehicle's fuel delivery system, leading to performance issues.
8. How long does it typically take to repair OBDII code P2066 Fuel Level Sensor 2 Performance on a Chevrolet?
The repair time for P2066 can vary based on the exact cause of the issue and the expertise of the technician. Simple repairs like sensor replacement may take a few hours, while more complex diagnostics could take longer.
9. Can a disconnected or loose fuel level sensor connector trigger OBDII code P2066 on a Chevrolet?
Yes, a disconnected or loose connector to the fuel level sensor can cause erratic readings and trigger P2066. It is recommended to check the connectors and wiring first when diagnosing this code.
10. Are there any preventive measures to avoid encountering OBDII code P2066 related to Fuel Level Sensor 2 Performance on a Chevrolet?
Regular maintenance and inspections of the fuel system, including the fuel level sensor and its connections, can help prevent issues that may trigger P2066. Additionally, keeping the fuel tank adequately filled can prevent unnecessary strain on the sensor.
Discuss the causes and fixes for P2066 Chevrolet OBDII Code
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We have seen GM brands throw certain codes that are attributed to internals on the gauge cluster going bad. I'm not sure if this has impacted the situation here, but 2003-2007 seem to run into similar stepper motor issues. GM gauge repair is my companies focus and we see ppl get killed over the prices on repairs, but its usually such a simple fix. Good luck! www.customautogauges.com
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