N52 Radiator Fan not working ?

M

munchkincoupe

Member
Car was in with my mechanic today and it overheated after having a road test and then left running following a health check. Car holds steady correct temp on driving with no issues. I haven't been in stop/start traffic yet. Car wasn't driving at the time of overheating so shouldn't have caused any issues.

They had enough time before closing to plug a decent diagnostic tool in and fault came back from electrical sensor for fan.

This car needs to be my daily driver from next weekend for 2 months so need to get this sorted this week and being a bank holiday is a bit more difficult.

I've done a search on here and other sites for N52 fan problems and come up with this shortlist - do you guys agree with these please?

- Fan - check for loose magnets or connections. If possible, apply direct power to the fan to see if it operates independently of vehicle controls. - if it doesn’t the fan motor is broken
X3 fan fits with some trimming of shroud - significantly cheaper that Z4 part

- Relay switch for radiator fan - test it by turning engine on, turn AC on - if fan doesn’t engage ? fan relay problem. located on lower radiator hose.

- Check A/C Pressure: Ensure that the A/C system is adequately charged. Low refrigerant levels can inhibit fan operation.

- Test Coolant Temperature Sensor: Unplugging the coolant temperature sensor should activate the fan if it's functioning correctly. If it does not, consider replacing this sensor.

- Inspect Electrical Connections: Verify that all wiring to the fan and related components is intact and free of corrosion or damage. ? Corroded green wire into the fan socket

- Examine Fuses and Relays: Check all associated fuses and relays for continuity and proper operation.
 
Having had four cars with N52 engines I wouldn't rule out a failed water pump for overheating issues.

But I think most Z4s use the same fan which isn't too expensive, unlike the M specific one I needed in 2022. After paying over £600 for one fitted in 2022 I discovered an X5 one can be adapted to fit!
 
Rule out the fan by stuffing 12 volts up it. I can't recall the last time i heard mine running, in normal driving at this time of year now its getting cooler you should be fine.
If you get stuck in traffic and you are worried then turn the heating up full and turn the engine off if you are going to be standing a while.
Keep a close eye on the gauge and it'll be okay.
 
Sounds that way! Make sure you are not trying to the turn the metal guard, you have to reach in a bit for the actual fan.
 
Rockhopper - you were right I wasn't going in far enough - that's what I get for trying to do it in the dark!!

fan spins freely - but with aircon on full whack with snowflake illuminated the fan does not kick in ? relay. It does blow cold though
 
I got my A/C regassed in 2021 but when the weather started to get warmer in 2022 it wasn't blowing cold. I took my car to RBM and they noticed my cooling fan wasn't working, although the car never overheated. Anyway it seems the refrigerant was getting too hot so over-pressurised and escaped via a pressure relief valve.

So I hope you can fix your fan issue. :thumbsup:
 
So I need to add check aircon ? Regas to potential causes too

I think one of my neighbours has a Carly - would that give a better diagnostic read
 
As a starter I’d be checking your green wire

Have a search on here as it’s a very common issue for it to fail
 
Ok so prioritised list when back in with mechanic this week would be the below:

- Inspect Electrical Connections: Green wire becomes corroded - Verify that all wiring to the fan and related components is intact and free of corrosion or damage. ? Corroded green wire into the fan socket - fix - solder in new wire section

- Fan - check for loose magnets or connections. If possible, apply direct power to the fan to see if it operates independently of vehicle controls. Can be tested inset if using INPA to power it on - if it doesn’t run the fan motor is broken - fix - new (used) fan part no. 67326925702 (one on its way)

X3 fan fits with some trimming of shroud - significantly cheaper that Z4 part if new one needed

- Relay switch/temp sensor for radiator fan - test it by turning engine on, turn AC on - if fan doesn’t engage ? fan relay problem. located on lower radiator outlet hose. Coolant will need to be drained and correct bleeding process for re-install - fix - new switch part no. 13621433077 ensure to replace O-ring seal too

- Check A/C Pressure: Ensure that the A/C system is adequately charged. Low refrigerant levels can inhibit fan operation - fix - regas


- Thermostat ?
 
Fans usually knackerd there is a few models of beemers much cheaper , put the aircon on , if it don’t kick in and it’s solid that will be it ! Really easy job to do remove the cover above the radiator it’s then a connector , one torx screw and a push fitting, carefully lift out and slot a replacement in and put it all back together
 
It was the green wire that was knackered - replaced and all working fine now. Will put the replacement fan in the for sale section.

Thanks for all the comments
 
You must log in or register to reply here.
Back
Top Bottom