As a noob here, I've been reading a lot of the threads about mechanical problems. Great, useful stuff, and sometimes scary.

I'm wondering if my second gen Justa has a cooling fan issue or not.

There appears to be no slow fan speed. If the fan runs, it's the noisy 'high' speed or nothing at all. Was MINI's solution for the troublesome resistor and slow-speed circuit in the first gen cars to just eliminate the slow speed circuit in gen two? There seem to be just two wires going to my fan, not three.

Relevant behavior:

- From a cold start, if the car is allowed to just idle, the fan seems to never come on, even after 20 minutes, in ambient temps around 70F. If I switch on the AC, the fan comes on within a few seconds (on 'high') and then shuts off if the AC is turned off.

- After normal driving in 70F weather, the fan will come on about a minute after the car is parked and the engine shut off. The fan runs for about a minute (again, on 'high') and then shuts off.

I figure the coolant around a temp sensor stops flowing when the engine's shut down, the coolant around the sensor then heats up a little, and that turns the fan on. Well enough, but should there be a slow fan speed like on the gen one MINI's? When the engine gets up to normal operating temp (at idle), should the fan be turning?

I'd like to know while I've still got warranty. It's an 09 MC.

 

There is no low speed fan on the R56 N12 engine. Just a high speed fan and it can come on anytime.

 

Thanks. I was hoping someone would say that!

 

I also have a '09 R56 and was curious about the same low-speed-fan question. I read in the new Bentley manual (for '07+ minis) that when the car first starts that the low speed fan comes on for about 20 seconds then shuts off. After reading that statement I thought I had a fan problem or the ECU wasn't sending a correct signal to the fan for it to engage. My fan also quits spinning once the temp has fallen below 90 degrees celcius. This is a Used car I bought so I don't have new ownership history with it.

If there are other R56 owners out there that can confirm that the low speed fan doesn't come on - even at the initial start phase - it would be good to hear from you.

Lastly, in the engine fuse box area there are two Fan Relays. Does anyone know why, especially in light of only the high speed fan supposedly being the only setting that works?

Thanks,

Max

 

I have tried to find the same answers you are requesting and made two posts on this issue. I don't know how to add a link to these posts, but you can do an advanced search for posts from byron h. The only two things I can add are that BMW states that only one temporature of the coolant activates the fan. There would have to be two temperatures if there was a two speed fan. Thanks for adding this information.

2011 MC (Justa), pepper white, sport seats, manual transmission

 

I posted this about a year ago, just after we got the car. Since then, by reading various threads, I've learned and figured out the following:

The first gen MINI's (before '07) had a "two-speed" fan. As the cooling system warmed up, reaching one temp turned on the low-speed circuit, and if the system continued to get warmer, at a higher threshold temperature the fan was powered by the high-speed circuit.

The high-speed circuit was just a direct electrical connection to the fan motor. But the low-speed circuit dropped the voltage supplied to the fan by putting a heavy-duty wire-round resistor in series with the fan. Unfortunately, this heavy duty resistor wasn't heavy duty enough for many MINI's and either the resistor or the leads attached to it burned out.

When that happened, the fan wouldn't run at all when the car's CPU called for low-speed. The cooling system would continue to warm up until it reached the higher threshold temperature, at which point the CPU switched on the high-speed fan circuit.

At low speed, the fan is barely audible. At high speed, it's pretty noisy.

Apparently, the genius solution to this for the second gen MINI was to just eliminate the low speed fan circuit altogether. Now, the fan runs either at the higher, noisy speed or not at all. I'm sure BMW engineers would explain the change was made to increase the MINI's performance by eliminating the weight of that heavy resistor.

And, apparently it's normal for the fan to come on in warmer weather after the car is stopped and the engine shut off. Mine will sometimes start up a minute after the engine is stopped, run for several minutes, and then shut off.

 

My first MINI was a 2007 MCS. This was a second genaration MINI and had a low speed fan. My 2007 MCS was fully loaded and included the climate control. The radiator fan was barely noticeable. My new MINI does not have climate control, just the base heating/AC system. I am certain my 2011 MC has only the high speed fan. I don't know if the change to a single speed fan came after 2007, or is just used on the base heating/AC system. It is also possible that the single speed fan is used on just the MC not the MCS. BMW changed the R56 engine from N12 to N16 in 2011. I assume there are some significant differences between the N12 and N16 engines.

2011 MC (Justa), pepper white, sport seats, manual transmission

 

If you read the Bentley manual for the 2007-2011 MINI, you will see that the fan speed is controlled by a pulse-width modulated signal from the ECM. No large hot power-wasting resistors as used in the first generation.

To quote the manual:
Electric fan activation is based on the following inputs to the ECM:
Radiator outlet temperature
Calculated catalytic converter temperature
Vehicle speed
Battery voltage
Calculated refrigerant pressure

So it is not a really simple system, thus matching lots of other features of the MINI.