2016 LTZ with 5.3 coolant temp regulator

[Geezer209]

I have a 2016 LTZ with 5.3 coolant temp regulator issue.

On two occasions over the past year the fans went to default and I had to disconnect the neg terminal on the battery.

(The first time it happened the passenger side Daytime Running Light also went out. I was told the light is fine but the power is not getting to it.)

Everything with the temp seemed to be fine. I later noticed the temp at idle was 210 but while driving at highway speeds it stays between 180-185.

Is this a problem and do you think the daytime running light being out is related?

Everything else seems to be fine.

 

[Fless]

Get a scanner on it and compare the ECT reading(s) -- there may be more than one engine coolant temp reading -- to see if the sensors are reporting properly. If the main ECT sensor is aftermarket you may want to try an OE one, and carefully inspect the connector and the pigtail for damage and fitment.

 

[adamztrucking]

Your 2016 LTZ's coolant temperature fluctuation and DRL issue may stem from related electrical or sensor faults. The fan default mode could indicate a faulty coolant temperature sensor, a sticking thermostat, or an ECU/electrical issue. The DRL not receiving power, despite the bulb being fine, may point to a wiring problem, fuse/relay fault, or a malfunctioning Body Control Module (BCM). Since the fan and DRL issues could share a common circuit or grounding point, they might be connected. Check the coolant sensor, thermostat, DRL wiring, and BCM, and scan for fault codes to diagnose and resolve the problem.