Greetings. I know this is a common topic and problem. I searched for answers and just can't find anything very similar to my situation...so I decided to post and pray for help.

Problem:
My radiator fan (stage 1 and 2) and my PSP fan do not come on. Ever.
I do NOT have AC hooked up, so I can not use that method to determine if stage 1 and PSP fan is working.

Attempted Solves:
- new PSP fan and connector (old one was stuck and connector was melted)
- new cooling fan installed (old one worked when I connect to 12V power source to it, but I wanted to be sure)
- checked all related relays and fuses...all working or in good shape.
- checked heat - heat works great (again, NO working AC on my car)

The engine does not overheat when driving or when sitting in normal stop and go traffic. It runs at about 188 F - 195 F almost all the time.
On higher heat days, it may climb a bit, but has rarely even gotten to the point where the low speed should be activated (213F).
I have a Scangauge2 to monitor temps.

After the new cooling fan was install, I started the motor on a hot day and let the temp get to 215 F (past low speed turn on)....221F....235 F (just past where the high speed fan is supposed to come on)...NOTHING happened...I took it for a cool down drive at that point and it returned to 192 F...Happy as ever.

What now?
- New thermostat (but if the heat works, is this a place I should be looking?
- New Coolant Temp sensor? Just not getting the message to turn the fans on?
- Go to the dealer?

Any ideas, suggestions, help would be great.
Happy Holidays and enjoy the Season!

TY
Geoff

 

pull the ct sensor plug, monitor the scangauge or obd port and verify the temp swing is one way or the other. identify which pins are for what... not sure if its a 5v sensor or what but determine what you need to do with the input to the ecu to simulate a boilover. then verify the ecu input to the fan relay toggles. if yes, debug downstream from there, if no, verify the wiring from the ecu to the relay.

you already know the sensor & wiring to the e u is working as expected so dont waste time there. give the ecu a reason to kick the fans on.

iirc the ps cooler fan is tied to the low fan relay, dont quote me on that though...

 

Thank you for the reply and ideas.

I must admit, I do not know where (or what) the CT sensor plug is. Do you mind providing a bit more detail?
I understand the concept of what you are saying, but have no idea on how to actually do it.
May just be over my head??

 

ok...after a re-read and re-think...
I know what / where the cooling temp sensor is...just not sure I can "ID which pins are for what" to simulate boil over...or how to actually do it.
this is part of the frustration with knowing enough to be dangerous...

Thanks again!

 

The CT sensor is a 2 wire plug according to the service manual... pull the plug, turn the key on and read the CT's... if they are below 0* then short the connector, then it should be maxed out which should kick on the fans.

 

feel your pain. electrical issue are difficult for me

my low speed fan comes on at 105c (221f). The high comes on at 115c (239f). not sure if that is all minis? I have a 2005 mcs r53. also have a 2006 base mini (son's car). seems to do the same.

you should get voltage at the fan plug when the temp goes above threshold.

also I can dig up a wiring diagram for you if you don't have one already. maybe that will help put the pieces together. never really does for me but...

not sure I helped you at all

 

For the record... that 105C is insane... it is no wonder why all of the seals dry up so fast and need replacing. the fan should be set to kick on at about 205*f.. If I get my butt in gear and get the ram controller done, the MINI controller will be identical. Both will use a pwm to gently control CTs to keep the current draw off the alt to a minimum.

(The Ram controller is done, needs to be installed and debugged on the target fans.)

 

Steve,

Thanks in advance for our patience and teachings...I am coming along.
By, "short the connector" do you mean put a 12V power source to it (pos to one pin and neg to the other)?

If that is what you mean, I totally get what you are suggesting and will try when I get back to the car in the new year.
If that is not what you mean, can you tell me how to short the connector? I do not have much electrical experience or understanding of the terms....I looked it up, but people are over the map in what they feel it means..

Thanks again!

 

ssoliman,

Ok, that makes sense too. I'll check that. I did check for power there, but not when the engine was hot enough. I wrongly assumed power was always running to fan and that the "on/off" mechanism was farther down the line.

I have the wiring info, but it does not do me much good for me....this is a bit of a hunt and peck process for me...ruling things out and moving on to the next. It has not been too critical as the car has been doing ok in the temp department...

Thanks for the reply and info.

 

No, what I mean by short the connector is to jumper both pins in the connector with a wire or paper clip. It will simulate the other end of the range, the ecu will think its 250* (example) and kick the fans on.

Edit: If your uncomfortable doing any of this then maybe send it to a shop? What your doing is making the ECU think the motor is overheating which will then kick on the fans

 

got it...100%....
- one wire with each end touching one of the pins in the connector...with the ignition on....
- fan should kick on...that then indicates the issue is the downstream from there (ct sensor, thermo)

thanks for the additional explanation.
also, thanks for the edit, I do have a few guys locally that may be able to help me.

 

No problem... comfort level comes with experience so have at it. Just check it first unplugged... OBD port should read one way or the other. IIRC on my Ram unplugged and the fan gets engaged, but thats a 5V sensor...