» Site Navigation | | » Recent Threads | | | | | | | 11-28-2016, 10:50 PM | #1 | Junior Member Join Date: Nov 2016 Location: Arizona Posts: 12 | Bmw 318ti cooling fan new question So I'm new to BMW but I have a new cooling fan question. So I bought my daughter a 318ti 1996 it has a 143000 miles and automatic. Here's the problem the fan only comes on with the a/c wait but it comes on with the a/c on and the fan is on LOW. I can jump it with the plug and a wire to her high fan speed but that's the only time there is high fan and there is only low fan with the a/c on. There is no fan with no a/c. Any help would be greatly appreciated. Oh yeah we did replace the whole cooling system i.e. Radiator,water pump,thermostat and housing and houses. Thanks again | | | 11-29-2016, 02:21 AM | #2 | Senior Member Join Date: Feb 2007 Location: Fl Posts: 1,353 | If I follow it sounds like you need a new fan switch. Quote: Originally Posted by New2bmw So I'm new to BMW but I have a new cooling fan question. So I bought my daughter a 318ti 1996 it has a 143000 miles and automatic. Here's the problem the fan only comes on with the a/c wait but it comes on with the a/c on and the fan is on LOW. I can jump it with the plug and a wire to her high fan speed but that's the only time there is high fan and there is only low fan with the a/c on. There is no fan with no a/c. Any help would be greatly appreciated. Oh yeah we did replace the whole cooling system i.e. Radiator,water pump,thermostat and housing and houses. Thanks again | __________________ SUPPORT 318ti.org! CLICK THE LINK ABOVE! Hosting a forum like this is not free. 318ti.org is one of the best BMW forums on the web because it is member supported, not vendor supported. The cost to become a Supporter is a nominal $10.00... A YEAR! DO IT! NOW! www.BimmerBum.com ALL NEW! 318ti Specific Parts For Sale www.facebook.com/BimmerBum BMWCCA #132203 95 318ti Club Sport 98 318ti Active S50 Swap | | | 11-29-2016, 03:18 AM | #3 | Junior Member Join Date: Nov 2016 Location: Arizona Posts: 12 | If your talking about the switch in the side of the radiator I replaced that as well when I replaced the cooling system. So as of now I have it temporarily spliced together so when the car is on it has full high fan on always. I tested both relays and have 12 volts at the high and low with either relay removed. If I unplug the plug that goes to the switch on the side of the radiator and turn the a/c on it still runs the fan on low? I also read that it should be on with ignition on car not started and a/c on but my fan is not on under those conditions. I only get low fan with car started and a/c on. Other then jumping high on with the plug. Any ideas? Thanks | | | 11-29-2016, 03:30 AM | #4 | Senior Member Join Date: Feb 2007 Location: Fl Posts: 1,353 | If you can make it work by bypassing the switch then you have likely found the problem. Have you tried letting it idle with the AC on and switch plugged in. There's the possibility that you are not getting the car hot enough to kick the fan into high speed. Quote: Originally Posted by New2bmw If your talking about the switch in the side of the radiator I replaced that as well when I replaced the cooling system. So as of now I have it temporarily spliced together so when the car is on it has full high fan on always. I tested both relays and have 12 volts at the high and low with either relay removed. If I unplug the plug that goes to the switch on the side of the radiator and turn the a/c on it still runs the fan on low? I also read that it should be on with ignition on car not started and a/c on but my fan is not on under those conditions. I only get low fan with car started and a/c on. Other then jumping high on with the plug. Any ideas? Thanks | __________________ SUPPORT 318ti.org! CLICK THE LINK ABOVE! Hosting a forum like this is not free. 318ti.org is one of the best BMW forums on the web because it is member supported, not vendor supported. The cost to become a Supporter is a nominal $10.00... A YEAR! DO IT! NOW! www.BimmerBum.com ALL NEW! 318ti Specific Parts For Sale www.facebook.com/BimmerBum BMWCCA #132203 95 318ti Club Sport 98 318ti Active S50 Swap | | | 11-29-2016, 03:39 AM | #5 | Junior Member Join Date: Nov 2016 Location: Arizona Posts: 12 | Only high works bypassing it and low only works with the a/c on. If I try and bypass to low it doesn't work. Also it's been this way through the AZ summer heat and only low on with a/c on and 112 outside literally. Also while I have you her car has always ran just past 12 on the gauge right next to the line the needle touching the right of the 12 mark. Everyone in here says they should run at 12 needle and line as one. I thought maybe when I replaced a the cooling system this would change but it didn't still ran exactly the same? Do some just run a tad hotter? Also I did use 50/50 BMW coolant when I replaced the radiator I self mixed I know it doesn't come that way. Thanks again for your replys. I've found a lot of difference's in these and American cars. My only complaint is this temperamental cooling system. Thanks again | | | 11-29-2016, 03:49 AM | #6 | Senior Member Join Date: Feb 2007 Location: Fl Posts: 1,353 | Got me on that one... Not sure how low works with the switch plugged in but does not work if you bypass the switch. Maybe look to the switch for the issue with the high and to a relay for an issue with the low. I had a failing relay cause the fan to stay on after the car was turned off and the key was out of the ignition. The factory temp gauge is really an idiot light with a needle. The gauge has about a 45 degree range where it will sit at the 12 o-clock position. If you really want to find out what temps are doing get an OBD2 port wifi adapter and use a smart phone app to monitor water temps in real time. __________________ SUPPORT 318ti.org! CLICK THE LINK ABOVE! Hosting a forum like this is not free. 318ti.org is one of the best BMW forums on the web because it is member supported, not vendor supported. The cost to become a Supporter is a nominal $10.00... A YEAR! DO IT! NOW! www.BimmerBum.com ALL NEW! 318ti Specific Parts For Sale www.facebook.com/BimmerBum BMWCCA #132203 95 318ti Club Sport 98 318ti Active S50 Swap | | | 11-29-2016, 12:36 PM | #7 | Senior Member Join Date: Aug 2009 Location: Georgia Posts: 595 | The fan will only run in low speed when the a/c is on. The only time the fan will run in high speed is when the a/c fan high pressure switch is made. Usually the high pressure switch will be closed when the a/c high side pressure gets over maybe 300 psi. When stuck in traffic and a/c full blast in Arizona heat. When a/c is off, once engine temp gauge goes over half, the fan should run in low speed. If it does not run in low speed with a/c off, there is a high speed fan relay with a normally closed contact that feeds the low speed relay. The high speed relay closed contact could be bad. Check the normally closed contact on the high speed fan relay first. __________________ 1996 Ti 280k miles and still going.... 1993 964 - holding on to this one 2001 Burban, 240k miles 2018 Suburban Z71 Last edited by bazar01; 11-29-2016 at 02:34 PM. | | | 11-29-2016, 08:59 PM | #8 | Junior Member Join Date: Nov 2016 Location: Arizona Posts: 12 | Is there a way to check that relay? | | | 11-29-2016, 09:57 PM | #9 | Senior Member Join Date: Aug 2009 Location: Georgia Posts: 595 | Yes. According to the schematics, K22 is the high speed relay and K21 is the low speed relay. Test both. Pull out K22 from the socket. K22 has two sets of contacts. NO and NC. (normally open and normally closed) Terminal 30 and 87a is the normally closed contact. Should have continuity. Terminal 30 and 87 is the NO contact. If you put 12V at terminals 85 and 86, the relay should pull in and the NC contacts will open and the NO contacts should close. K21 only has a normally open contacts (NO) So you cannot switch these two relays. __________________ 1996 Ti 280k miles and still going.... 1993 964 - holding on to this one 2001 Burban, 240k miles 2018 Suburban Z71 Last edited by bazar01; 11-29-2016 at 09:59 PM. | | | 11-29-2016, 10:27 PM | #10 | Senior Member Join Date: Aug 2009 Location: Georgia Posts: 595 | Power distribution chart. __________________ 1996 Ti 280k miles and still going.... 1993 964 - holding on to this one 2001 Burban, 240k miles 2018 Suburban Z71 Last edited by bazar01; 07-10-2017 at 01:43 PM. | | | 11-29-2016, 10:34 PM | #11 | Junior Member Join Date: Nov 2016 Location: Arizona Posts: 12 | Ok thanks I'll try that. I didn't switch the magenta and yellow ones I switched it with the a/c one and the a/c still worked. If I can't test it I'll update when the new one arrives. Thanks oh I had one other question for you is the cooling system to bleed really that finicky? I've done it several times and I keep losing heat the heater. And the needle going above 12 by a line if I open the bleeder screw let off some steam it cools right down? The coolant and oil look great no mixing and no change in level? I checked these because my first thought was head gasket? It's been a great car I really like the engineering just this cooling system has been a nightmare. Thanks again for your replys | | | 11-29-2016, 10:41 PM | #12 | Senior Member Join Date: Aug 2009 Location: Georgia Posts: 595 | Quote: Originally Posted by New2bmw Ok thanks I'll try that. I didn't switch the magenta and yellow ones I switched it with the a/c one and the a/c still worked. If I can't test it I'll update when the new one arrives. Thanks oh I had one other question for you is the cooling system to bleed really that finicky? I've done it several times and I keep losing heat the heater. And the needle going above 12 by a line if I open the bleeder screw let off some steam it cools right down? The coolant and oil look great no mixing and no change in level? I checked these because my first thought was head gasket? It's been a great car I really like the engineering just this cooling system has been a nightmare. Thanks again for your replys | Ok. If you switched the a/c and low speed relays, K21 and K19, you shd be ok. They are the same configuration with just a NO contact. There is no other relay the same config as K22. You have to test it and see if the contacts are both good especially the NC contacts. I never had any problem bleeding my 1996 when I replaced the plastic cooling parts, hoses, radiator fan and radiator. You may need to get the cooling system pressure tested to rule out head gasket or cracked cylinder head problem. __________________ 1996 Ti 280k miles and still going.... 1993 964 - holding on to this one 2001 Burban, 240k miles 2018 Suburban Z71 | | | 11-29-2016, 10:55 PM | #13 | Junior Member Join Date: Nov 2016 Location: Arizona Posts: 12 | I did replace all the parts water pump,thermostat and housing,radiator,hoses. With head gasket wouldn't coolant be in the oil? Thanks again for everything | | | 11-30-2016, 01:18 AM | #14 | Senior Member Join Date: Aug 2009 Location: Georgia Posts: 595 | Quote: Originally Posted by New2bmw I did replace all the parts water pump,thermostat and housing,radiator,hoses. With head gasket wouldn't coolant be in the oil? Thanks again for everything | In some cases coolant gets in the oil and you get a milkshake in the oil pan. But in some cases, oil which is at a higher pressure, gets into the cooling system and shows up in the coolant reservoir and radiator. The coolant reservoir can also get filled up and get pressurized and show signs of oil contamination. You can loan a coolant pressure tester from a nearby auto parts store. They usually just require you to put a deposit which is refundable upon return of the tool. __________________ 1996 Ti 280k miles and still going.... 1993 964 - holding on to this one 2001 Burban, 240k miles 2018 Suburban Z71 | | | 11-30-2016, 02:00 AM | #15 | Junior Member Join Date: Nov 2016 Location: Arizona Posts: 12 | Yea I know I'm not getting any of that though. I'm new to BMW not cars I've been building classics and trucks for 25+ years. All v8's single cam and no foreign. My confusion is that there's no symptoms other then the highly pressurized cooling system. I bled it again and have heat that will cook you inside now. So I'll let my daughter drive it to work a couple days and see if it maintains. Thanks for all the info | | | | | Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | | Posting Rules | You may not post new threads You may not post replies You may not post attachments You may not edit your posts HTML code is Off | | | |