Temp Gauge

[Mickalo]

Gotta strange one, 2019 Titanium 2.0 temp gauge the last few days seem to flutter up and down doesn't over heat heater works great fluid level good radiator cap seems in good shape but the gauge bouncing up and down maybe a gauge sender unit issue

TIA

[Wubster100]

Engine coolant flows primarily from the engine to the radiator circuit and back to the coolant pump. Coolant is sent from the coolant pump through the engine block and cylinder head. Separate circuits from the engine also feed the heater core and turbocharger with coolant. The coolant pump, operated by engine rotation through the accessory drive belt, circulates the coolant. The coolant thermostat is a control valve actuated by coolant temperature. When the thermostat is closed, coolant flow bypasses the radiator circuit and returns to the coolant pump. When the thermostat is opened, coolant flows through the radiator circuit to transfer engine-generated heat to the outside air.

 

The engine uses a cold side thermostat. This means the thermostat is located at the lower radiator hose connection to the engine, where coolant enters the engine after being cooled by the radiator. During initial warm-up, the cooler coolant from the radiator quickly closes the thermostat after the warm coolant in the engine opens the thermostat slightly. The thermostat opens and closes several times before the coolant coming from the radiator is warm enough to allow the thermostat to remain open. The engine must run much longer than a vehicle with a hot side thermostat before the thermostat remains fully opened.

 

The degas bottle holds surplus coolant and removes air from the cooling system. It also allows for coolant expansion and system pressurization, replenishes coolant to the cooling system and serves as the location for service fill.

 

The thermostat monitor is a function of the PCM and is designed to verify correct thermostat operation. The monitor executes once per drive cycle and has a monitor run duration of 300-800 seconds. If a malfunction occurs, DTC P0125 or P0128 sets, and the MIL illuminates.

 

Temperature Gauge

If the engine coolant temperature data or engine overheat indication request messages are missing for less than 5 seconds, the IPC defaults
the temperature gauge to the last indication state, based upon the last message received.

 

If the engine coolant temperature data or engine overheat indication request messages are missing for 5 seconds or longer, the IPC defaults
the temperature gauge to the full hot position.

 

Indication Range

0% (under 38 °C [100 °F]) - Full cold (C)
15% (60 °C [140 °F]) - Beginning of the normal range
45% (823 °C [180 °F]-110 °C [230 °F]) - Center of the gauge
85% (120 °C [248 °F]) - End of the normal range
95% (123 °C [255 °F]) - Hot (H) (red line)

 

Engine Fluid Temperature Management

The engine fluid temperature management can be activated when high temperature or high load conditions take place. When the engine fluid temperature management is activated, the PCM sends a controller area network (CAN) message to the instrument panel cluster (IPC). The IPC then displays a power reduced to lower temp message. The engine coolant temperature gauge needle moves toward the H (hot) zone. In order to manage the engine's fluid temperatures, the PCM starts to reduce engine power and vehicle speed. The air conditioning may cycle ON and OFF to protect overheating of the engine.

 

Cylinder Head Temperature (CHT) Sensor

Engine Coolant Temperature (ECT) Sensor

 

[Wubster100]

I don't have my temperature gauge displayed on mine, so I would have no idea if my temperature gauge fluctuates.