Fault code 15 - Struggles to start

[BazaJT]

Can anyone confirm that engines after 08135541 should have a black CTS? My engine is 08461362 and has a blue CTS so maybe the wrong one has been fitted in the past[my car is a F/L 3.0]

[Doctor Gollum]

Can anyone confirm that engines after 08135541 should have a black CTS? My engine is 08461362 and has a blue CTS so maybe the wrong one has been fitted in the past[my car is a F/L 3.0]

Does it work?

[dave the builder]

You can't just say it needs a blue one or a black one , there are so many aftermarket manufacturers that use different colours for the same part .
I've seen blue, grey, natural and black

[BazaJT]

Well DG the engine starts and runs the fans kick in[all three at the same time]and then don't stop until after the engine has been turned off.Air con doesn't work[never has since I've owned it]but the fans did used to behave as they should,so something isn't right.

[Doctor Gollum]

The fans are almost completely independent of the ecu. There's two thermoswitches on the radiator. These are the primary fan controls.

The only time the ecu would request the fans is if the aircon is switched on, no aircon means that the fans are self regulating

I forget which thermoswitch controls which fans, but it stands to reason that if one is failing, tother won't be far behind, so would swap both and report back

The aircon not working may also be related, depending on the cause, and not having it working makes diagnosis of the fans a bit harder as the aircon wiring is directly connected to the fans... that's to say the aircon not working could be electrical rather than just low refrigerant

[Eyal2002]

The thermoswitch activates the fans that are on the radiator towards the engine. When looking at the radiator from the engine side the thermoswitch plug is visible. If disconnected, the plug (2 or 3 contacts) can be safely shortened with a paperclip or wire (one is ground, other wires receive that ground for half/full fan speed). If all is healthy (fuses etc) then the two said fans should kick in regardless of key/ignition position.

[BazaJT]

Don't know original reason for air con not working but the bearing for the pulley on the compressor is now shot so I've fitted a shorter non-aircon auxilliary belt to by pass the compressor.From what I can see the lower thermoswitch would need the radiator to come out to get the clearance for a spanner? I know the top switch is a three pin on mine.

[Eyal2002]

I don't know about lower thermoswitch, I don't have it (2.6L), or if it is indeed one (maybe temp sensor?).
Anyway the 3-pin one is controlling the fans. Again, make a temporary U-shape from a metal clip, unplug it and short the ground to any of the others. You can send a temporary wire from the battery negative terminal to each one of the three, two of the wires should respond by turning the fans on, and if so then the one not responding is the plug's ground.
Note that as this is always a live plug, if you short it with a paperclip and fans are on then it can deplete your battery after a good few minutes. And of course always EXPECT the fans to kick in, so before troubleshooting clear them from wires, tools, fingers etc.

[Doctor Gollum]

The lower one may be region dependent...

UK cars have 2