Chevrolet Silverado 1500 Coolant Temperature Sensor Guide (2016-2021)
Is your Silverado's temperature gauge acting up or are the cooling fans always running? Here’s what you need to know.
- The most common problem, code P0128, is usually caused by a faulty thermostat, not the sensor itself.
- It is highly recommended to replace the sensor and thermostat at the same time since they are located together.
- Symptoms include fans running constantly, an incorrect temperature gauge, and the A/C not working.
- This is an easy and inexpensive DIY replacement that most owners can perform in under an hour.
Is It the Sensor or the Thermostat? The P0128 Code Issue
If you own a 2016-2021 Silverado, the most common issue you'll encounter related to the cooling system is a check engine light with the code P0128 - Engine Coolant Temperature Below Thermostat Regulating Temperature. While this can point to the sensor, it is far more likely that the problem is a thermostat that is stuck open. When the thermostat is stuck open, the engine takes too long to warm up, which triggers the code.
🎬 Watch: A mechanic explains why the P0128 code triggers.As a fail-safe, your Silverado's computer will react to a P0128 code by turning the cooling fans on high speed and disabling the air conditioning. Many owners also report the temperature gauge getting stuck at 160°F and not moving.
Pro Tip: Replace Both at Once
Since the Coolant Temperature Sensor is located right next to the thermostat housing, most mechanics and experienced owners recommend replacing both the thermostat and the sensor at the same time. The sensor is an inexpensive part, and replacing it along with the thermostat can save you from having to do the same job twice down the road.
🎬 See this step-by-step guide for replacing the thermostat assembly.Choosing the Right Aftermarket Sensor
For a straightforward part like a coolant temperature sensor, a quality aftermarket replacement offers excellent value. The technology is not complex, and manufacturing standards for these components are high. Brands like Standard Motor Products or other direct-fit replacements provide performance and reliability that are very close to the original part for a fraction of the price. Since the sensor is a low-cost item, choosing an aftermarket version is a smart way to save money, especially if you are also replacing the more expensive thermostat assembly.
Cost Comparison
| Part Type | Price Range |
|---|---|
| New OEM (ACDelco) | $18 - $30 |
| New Aftermarket | $20 - $21 |
| Shop Labor | $80 - $160 |
Frequently Asked Questions for Silverado Coolant Temp Sensor
Where is the coolant temperature sensor located on a 2016-2021 Silverado?
The sensor is on the driver's side of the engine, near the front. You will find it threaded into the engine block or thermostat housing, just below where the large upper radiator hose connects. You will likely need to remove the plastic engine cover and air intake duct to get clear access.
Can I replace the sensor myself?
Yes, this is a very DIY-friendly job that can be done with basic tools. The process involves letting the engine cool completely, disconnecting the battery, removing the air intake tube for access, unplugging the sensor, and unscrewing it with a 19mm deep socket. 🎬 Watch: How to replace the coolant temperature sensor yourself. Be prepared for a small amount of coolant to spill out.
What tools do I need to replace the sensor?
You will need a ratchet with an extension, a 19mm deep socket, a flathead screwdriver or 8mm socket for the intake hose clamps, a drain pan to catch coolant, and some rags. It's also a good idea to have some pre-mixed DEX-COOL coolant on hand to top off the system after you're done.
Are there any recalls for this issue?
No, as of early 2026, there are no active safety recalls from GM or NHTSA for a faulty coolant temperature sensor or the common P0128 thermostat issue on the 2016-2021 Silverado 1500. This is considered a standard maintenance or repair item.
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Technical Specifications
OEM Part Numbers: 12608814 12673064 12650595
Located on the driver's side, near the thermostat housing. Requires a 19mm deep socket for removal. The connector is a 2-pin plug-in type.
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Chevrolet Silverado 1500: