Holden V6 3.6L (HB) LEO-2004 Lumina Station wagon- Cooling fans coming on too late?

[JohannesM]

Holden V6 3.6L VZ (HB) LEO-2004 Lumina station wagon, when in slow traffic or standing still idling the temperature seems to increase quickly to almost red. Once I get moving the temperature will drop down. Only one fan comes on, without the aircon on the drivers side fan will come on immediately when switching on the aircon. Without the aircon that fan will eventually come on when temperature reaches over the half way indicator. I did check the other fan and it is working ok. There is 12V supply going into that (passenger side) fan but it does not activate when temperature increases to very high. I suspect it may be a temperature sensor but not certain or where this is located. I have checked the fluids are ok. Not certain where to proceed from here.

 

[lout]

check/replace fan 1 relay

 

[JohannesM]

Thank u for your input.

 

[JohannesM]

Where might this fan 1 relay be located?

 

[lout]

under bonnet relay box

 

[krusing]

Possibly the Temp Sensor
TS located in behind oil filter housing, on bank 2 just below the cam cover.
Check the connector also,
As the heat from the exhaust manifold makes them brittle and destroys them over time.

 

[JohannesM]

Possibly the Temp Sensor
TS located in behind oil filter housing, on bank 2 just below the cam cover.
Check the connector also,
As the heat from the exhaust manifold makes them brittle and destroys them over time.

Thank u. Will check it out.

 

[JohannesM]

Possibly the Temp Sensor
TS located in behind oil filter housing, on bank 2 just below the cam cover.
Check the connector also,
As the heat from the exhaust manifold makes them brittle and destroys them over time.

Thank u, will check this as a possible cause.

 

[krusing]

I’m not saying it is that,

But checking it first would be the first (cheapest) option,
If you can, remove it as it may be covered in crud, which may cause it to malfunction at the correct temp.

 

[krusing]

Side note:
Recently I had the temp sender on my LY7 fluctuate,
(and I had already replace the thermostat)
and I checked the TS connector,
and it fell to bits,
So I source a replacement (s/hand) plug and I spliced it on the existing wires/loom.
And haven’t had a issue since.