u/Educational-Bit9483

My aux fan runs at full speed even with the engine off.

The story:

My alternator died, and the shop found that the cluster and aux fan died too (the fan connector was a bit burnt at the aux fan).

The shop changed the fan.

I did the alternator and cluster myself. The fan would not run until the cluster was changed.

On the way back from picking up and swapping my cluster, the fan was working fine. During a car wash, suddenly the fan started running full speed and won't stop unless I manually disconnect it.

Now my other local shop said it could be the fan or the cluster.

I myself am not sure but I checked the coolant temperature outlet sensor and it's fluctuating randomly. I have already changed the sensor and still getting this fluctuation.