Radiator Fan question

[BHP231]

Sorry if this is a very basic question...
The car ('85 944) is quite new to me and other than driving it from Sydney to Melbourne (9hours) it's generally been in storage, other than taking it out to do a few things.
Yesterday I started out on a drive and after a couple of miles I noticed the engine temp gauge needle pointing to cold, not moved at all. I went a little further and it still didn't move so I went straight home. With the car idling in the driveway I popped the bonnet and I couldn't see the two radiator fans working. I left it to run for several minutes but the fans and gauge still didn't want to work and it was a pretty hot day.
With the engine off I can turn them by hand so they aren't seized, is this normal? Should the fans and engine temp gauge start moving earlier or do I need a longer drive (and risk overheating?)

Just looking to hear some feedback before I start pulling fuses and relays out and generally making things worse.
Thanks.

[massive]

Something definitely isn't correct.

There are two temp sensors you need to check. One on the radiator and one on the engine block.

The engine block sensor is linked to the temp gauge in the dashboard.

The sensor on the radiator is just a thermo switch that activates the fan when the coolant gets to a certain temperature.

[BHP231]

Thanks for the reply. And great blog, I'm sure I will be checking my hat shield and engine mounts in the near future too!

[9FF]

Check both fuses. Do the fans come on with the AC switched on? The AC on bypasses two problem prone resistors in the circuit to check if they are the issue. Second, try removing and reseating the coolant fan relay, the largest relay in the fuse box nearest to the cabin bulkhead. Third, ground each wire that goes to the thermoswitch on the top of the radiator. Fourth, apply power and ground directly to each fan to check they are actually serviceable.

Like massive said, the fan circuit and the gauge circuit are not connected, so you have two unrelated problems. I'm only giving you checks for the fan circuit.

[BHP231]

Thanks. I've got the fan going so just leaves the gauge now. Fuse box is very different to the manual lay out so will take a longer look when I get some more time.

[BHP231]

Update. Went for a longer drive today and was happy to see the temp gauge needle move to the normal position.
Later in the drive I noticed it had reverted to the no temp reading position (far left in gauge).
So, it appears to work intermittently.
Any further ideas on this please?

[9FF]

Originally Posted by BHP231

...Any further ideas on this please?

It's either the guage, the sensor or the wiring. Check the connection to the engine block sensor is good, if that's ok replace the sensor its an easy 15min job.

[BHP231]

Ok thanks.