P0668 GMC Code - Control Module Temperature Sensor Circuit Low Voltage
Quick Answer
The Transmission Control Module (TCM) temperature sensor is located inside of the control solenoid valve assembly which has no serviceable parts. Common causes include Faulty Control Solenoid Valve Assembly, Control Solenoid Valve Assembly harness is open or shorted, Control Solenoid Valve Assembly 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
- P0668 GMC indicates Control Module Temperature Sensor Circuit Low Voltage.
- Common causes
- Common causes include Faulty Control Solenoid Valve Assembly, Control Solenoid Valve Assembly harness is open or shorted, Control Solenoid Valve Assembly 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 P0668 GMC Description
What are the Possible Causes of the DTC P0668 GMC?
- Faulty Control Solenoid Valve Assembly
- Control Solenoid Valve Assembly harness is open or shorted
- Control Solenoid Valve Assembly circuit poor electrical connection
How to Fix the DTC P0668 GMC?
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 P0668 GMC 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.
Need more information about the P0668 GMC code?
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Information for Specific GMC Models
- P0668 2014 GMC Sierra — Control Module Temperature Sensor Circuit Low Voltage
- P0668 2015 GMC Sierra — Control Module Temperature Sensor Circuit Low Voltage
- P0668 2016 GMC Sierra — Control Module Temperature Sensor Circuit Low Voltage
- P0668 2017 GMC Sierra — Control Module Temperature Sensor Circuit Low Voltage
- P0668 2018 GMC Sierra — Control Module Temperature Sensor Circuit Low Voltage
Frequently Asked Questions about P0668 GMC Code
1. What does the OBDII code P0668 mean on a GMC vehicle?
P0668 indicates a low voltage issue in the Control Module Temperature Sensor Circuit, which monitors the engine control module (ECM) temperature to ensure proper operation.
2. What are the common symptoms of code P0668 in GMC vehicles?
Symptoms may include engine performance issues, poor fuel efficiency, illuminated check engine light, or potential overheating of the control module.
3. What causes the P0668 code to appear in GMC vehicles?
Common causes include a faulty control module temperature sensor, damaged wiring or connectors in the sensor circuit, or an issue with the ECM itself.
4. Can I drive my GMC with a P0668 code?
Driving with this code is not recommended, as it may lead to engine performance issues or damage to the ECM if the problem is not addressed.
5. How do I diagnose the P0668 code on my GMC vehicle?
Start by inspecting the wiring and connectors for the control module temperature sensor, checking for damage or corrosion. Use a multimeter to test the sensor and circuit for proper voltage and resistance.
6. What repairs can fix the P0668 code in a GMC?
Repairs may involve replacing the control module temperature sensor, repairing or replacing damaged wiring or connectors, or in rare cases, replacing the ECM.
7. How much does it cost to fix the P0668 code on a GMC?
The repair cost depends on the issue. Replacing a temperature sensor may cost $50-$150, while ECM replacement can range from $500-$1,500, including labor.
8. Can a dirty or corroded connector cause the P0668 code?
Yes, dirty or corroded connectors can disrupt the sensor circuit, leading to a low voltage issue and triggering the P0668 code.
9. Is the ECM temperature sensor the same as the engine coolant temperature sensor?
No, the ECM temperature sensor specifically monitors the temperature of the engine control module, while the coolant temperature sensor monitors the engine's coolant.
10. Will clearing the code with a scanner fix the P0668 issue?
Clearing the code may turn off the check engine light temporarily, but the underlying problem must be resolved to prevent the code from returning.
Discuss the causes and fixes for P0668 GMC OBDII Code
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