Hi,

I've seen a few posts here about radiator/condenser cooling fans working, not working, working intermittently, coming on late, etc. Haven't seen one about this problem.

Our 2003 X-type 3.0 cooling fans come on within seconds after starting the engine, then race at the highest speed until the engine is shut down. You can hear it a 100' away.
-Winter or summer.
-Coolant level good.
-Temp gauge indicates temp and sending unit good.
-Happens whether Climate control is on or off.
-No MIL set or code pending.

Interesting tidbit: When ignition is switched on but engine not started, fans slowly start up and then slow to a stop every 10 seconds or so.

Fan assy's are available aftermarket, but without the control module, and that is only from Jag at $350 or thereabouts. Lot to spend if not sure.

Ideas?

THanks,

Tom

 

glainc, from what you are describing, it sounds like to me that there is an internal problem inside of the ECM. If you want to help prove this, let me know. It will involve using a multimeter to check a wire for voltage.

 

Yes, please.

 

One more data point.
Sometimes if you shut the engine down and restart, the fans stay off, maybe even until the next time it is restarted.

 

glainc, you will need to access the fan controller near the battery. You are looking for a 2 wire plug that has 2 small wires running to it. The wires are a white/gray wire and also a white/blue wire. The wire you are after is the white/blue wire. You will want to undo this plug and then using a multimeter measure the white/blue wire to chassis ground measuring VDC. Start the car and turn off the A/C-heat system to ensure no signals are being sent to the fan controller due to the A/C-heat. Now, with the multimeter connected up, read what the voltage is. If you are getting 0 VDC (or something under 1 VDC), then your ECM is functioning properly and it is telling the fan controller to not run the fans. This would leave the problem being a bad fan controller. If you are getting 12 VDC (or anything above 8 VDC), then you have a problem inside of the ECM and either need to have the car professionally looked at or do some more investigation of the wiring to ensure you don't have a damaged harness that is forcing 12 VDC on to the white/blue wire. After that, replacement of the ECM would be required.

 

Thanks.
Easy enough. I'll report back afterward.

If I need an ECM, maybe I can find a reman unit. BTW, where is the ECM on this car?


Tom

 

glainc, if you open the hood, you will need to remove the cowl from just in front of the windshield. Then, if you look in the corner near the passenger side hood hinge, it will be the computer box sitting right there.

As a side note, if you are getting battery voltage, you may have a wire that is touching the data line (the white/blue wire) going to the fan control module. So, before you just go swapping out an expensive ECM module, a little bit of looking at the wiring may be advisable.

 

you might want to double check if both fans are working. i had the same problem last week and when i checked, only one fan was working. it turned out that the code from the module to the top fan detached. pushed it back in and the fans are running as they are supposed to.

 

My 02 xtypes fans kickin about 10 secs after I start the car and run wide open most of the time. for about 2 days they seemed to work right( didnt cut on till gauge was at half way and turned off after a couple mins). sometimes I hear them slow down. I checked the voltage at the blue/white and when key is off I get battery voltage 12 or so . Start it and after 10 secs I get 1.3 and fans kick in. I turn on AC and it increases to 3.5 and when i turn AC off it drops to 1.3 and runs continuously( both fans) Thermo what do ya think. Also I noticed that the idle speed of engine drops a little when they turn off so I was wondering if maybe the remote AC module could be affecting it because most cars idle kicks slightly up when u turn on ac...

 

On my 03 x-type both fans run at full speed at times when they shouldn't be. It has been rather intermittent. They will run at full speed for several days until I pull out the meter to check the duty cycle on the wire (white/blue) from the ECM. Then it works correctly until I put the meter away. Did manage to catch it once when I first started it cold. The signal from the ECM was at 7% and both fans were running at full speed. Normal operation seems to be 7-9% when the fans are off and 9-16% when the fans are cycle between slow and off when warm and sitting idling for awhile. So I'm leaning towards the fan control module is going bad but would like the get a few more measurements or find out if this is a common way of failing before spending the money on a new control module

 

Had this same problem... the controller on the fan assembly was at fault... and stupid money to replace. Bought a whole new fan assembly from a wreckers yard, fitted this with crossed fingers re the controller on this... everything ok

 

On my 03 the controller went out( no fans) found one in outer Minnesota,they sent me one from a 08, all the wiring was wrong,I was faced with rewiring the new one or finding the correct one. I called them, they knew what they did and scoured the country for a 05 , they found the last one around in another town, had it shipped to me n/c and sent me a return slip for the 08 one. The 02 thru 04 ones have a weak component that can't be replaced easily( per the internet) but the 05 year they fixed it and it's a perfect match. Thats the one I got. That was in July, all OK after a couple day delay,been good since. They don't get much use at -10 deg around here. LOL

 

On a further note, The 06 thru 09 will work but you have to buy a adapter cable for another $30/$40 or a whole fan assy. They won't separate the controller from a GOOD fan assembly, it's all or nothing but they WILL sell the fan assy without the controller.It's supply and demand????

 

I have had similar issues, after fixing manifold air leaks and forward O2 sensor I got to a point where the only issue was fans running, I have been in contact with turbo (Chris) previously and carried out tests as per his instruction cheers Chris, I did replace the module with new one from China, my original issue was one day after a drive both fans were running full and flattening battery with or without engine running hot or cold ign or not, replaced module fans then ran when ign turned on and went off after key removed for few seconds, I could live with that, then everything started working properly on some days fans would only come on when temp demanded them or A/C turned on but then would revert to being on all time with ign on.
yesterday the temp gauge which has never gone above mid-range suddenly went to almost red, I pulled over killed engine and left ign on, no fans operating hoses fit to burst with pressure, I had no tools so had to wait to cool down, my theory I would get home (not far) in leaps and stop to cool when needed but when I pulled away the temp went back to normal and I could hear the fans running so carried on to get home.
today I checked connections, battery and earths etc. no codes no leaks, no coolant loss, belts all good everything looked ok so I left ODBC on to keep track of temp and started car, let it run to temp, gauge rose gradually to normal but ODBCII saw temp continue to rise to 106degrees and no fans cut in not even when I turned on A/C so I turned off engine to cool, when I can get my big hands near enough I will check values again but all these problems seem to me like electrical gremlins very hit and miss and intermittent and a real headache.
I don't want to start using bodges to install additional manually controlled fans to reduce temp I would rather have her work the way she is meant too.
as usual guys any help appreciated.
OK she has cooled enough to work on, I checked the blue/white wire and getting 0.12v not exactly cold engine yet though so I replaced the module with second one I bought at same time from China (no disrespect but they were cheap so got two) volts still 0.10v and now am back to where I started? almost, fans coming on full with ign, speed reduces when A/C turned on, I can at least now run her again and see if things settle or go wrong over next few days.
I hate electrical gremlins so now Iam wondering why I put a deposit on a new tesla model 3 lol