Radiator fan won't stop

[danielk]

Hi,

I've got a problem with Signum 1.9CDTi 2004. My radiator fan won't stop working, even when the key is not in ignition. As expected it drains a battery.

Is there any sensor, switch faulty or this is some kind of short circuit? Any advice how to check it and fix it?

Thanks a lot in advance.

Dan

[James24]

I'm not sure which sensor tells the fans to run, probably the coolant temperature sensor. Is your temperature gauge working normally? Mind you, I think the Vectra fans go off when the ignition is turned off, so that may not be it but perhaps worth checking anyway.

Maybe you could check you handbook for cooling fan fuses and pull them out until you get the problem properly fixed to save your battery? Fuses 35 and/or 36 (depends on which engine you have as to which fuses you have and what rating they are) in the fusebox under the bonnet next to the battery look like 2 to try first.

[danielk]

but does the fan run even when engine wasn't on? it's -2 outside engine is ice cold and wasn't even started. when I connect the battery fan is working on full speed with engine off. when engine is running fan speed is much slower but still working all the time.

i'm just thinking how to troubleshoot the problem. i'm sure it's something silly and taking this to the garage will cost a fortune

[James24]

but does the fan run even when engine wasn't on? it's -2 outside engine is ice cold and wasn't even started. when I connect the battery fan is working on full speed with engine off. when engine is running fan speed is much slower but still working all the time.

i'm just thinking how to troubleshoot the problem. i'm sure it's something silly and taking this to the garage will cost a fortune

I don't think the Vectra fans run when the ignition is off like on some other cars as per my previous post. I suspect it's a short circuit allowing power to the fans when it shouldn't, or an ECU fault telling them to run all the time instead of switching them on and off.

Pulling the fuses out will stop the fans - and save your battery - until you have diagnosed and fixed the problem

Does you car show and fault lights or fault codes? Can you check the wiring to the fans to see if it looks to be damaged? Does your temperature gauge act normally? This will tell you if the coolant temperature sensor (which may be what turns the fans on and off) is working OK.

How many fans does your car have (probably 2) and which one(s) of them are running all the time?

Hopefully someone will be along soon who can advise more on possible causes.

[danielk]

will check the temp gauge tonight ... and get the fuse out for time being.

thanks for advice

[danielk]

The temp gauge doesn't work at all.

[Das]

Have you tried disconnecting the plug from the sender unit on the thermostat?

[macdad]

Dont know if this is any good to you bud but this is what it states in the manual....

"The electric cooling fan,mounted on the rear of the radiator is controlled by the engine management system electronic control unit in conjunction with a cooling fan module.At the a predetermined coolant temperature the fan is actuated".

Hope this helps...been trying to find out where the "cooling fan module " lives,but it doesn't say exactly where it is..maybe another member might know.

[m8internet]

This was also a common fault on the Vectra B
Happened to me once, parked the car, the radiator fan was blowing which can be normal on a hot day
However, I returned about an hour later and it was still on
Used the car and it didn't happen again
However, the fault returned a few days later
Drove to VX dealership, and the fan remained on all the time
Traced to a failed relay
Also known to flatten the battery

[danielk]

Have you tried disconnecting the plug from the sender unit on the thermostat?

I haven't tried but will do it tomorrow