» Site Navigation | | » Recent Threads | | | | | | 07-15-2011, 07:11 AM | #1 | Junior Member Join Date: Jul 2011 Location: Australia Posts: 12 | Aussie chick with 318ti G'Day all, I joined this forum hoping to find useful info on maintenance and mechanical/electrial troubleshooting specific to my right-hand drive 1996 318ti compact (E36/5). Searching for answers has been quite frustrating so far, as the specific heating/air con issue I'm investigating may or may not relate to something referred to as the "Temperature wheel switch" in various wiring diagrams I've found. These wiring diagrams may or may not be applicable to my car, which does not have a Multi-Information Display (MID) in the centre of the dash, and which has only three large dials in the centre of the dash for fan speed, temperature and defog/face/feet air vents, as opposed to the heating and a/c control module in the dash centre of other E36 models. Grrrrrrr! I will search around and see if there are any threads which can point me in the right direction. If you happen to know what I'm going through, and might be able to help me find the right manual/forum post/blog for dismantling and investigating wiring issues in the centre dash of a 318ti (E36/5) with three dials and no MID - please let me know!! NB: I already have a Bentley 3 series manual which does not help in this case, and I have looked at the 1996 BMW E36/5 compact (318ti) Electrical Troubleshooting Manual available from the wedophones site [although admittedly I may be interpreting it wrong!]. Despite annoying issues like total lack of air con/heating, saggy hood lining and completely shot bonnet and boot struts, I absolutely love my 318ti See you round the forum! | | | 07-15-2011, 03:42 PM | #2 | Senior Member Join Date: Dec 2007 Location: Gulfport, Florida Posts: 3,208 | I would like to help but I don't think the temp wheel switch has anything to do with your issue. Maybe it does but I don't know how far you have gone into trouble shooting this issue... You need to check fuses and ensure the fan motor is good since the fan motor is not working for heat or A/C. Fuses first, ok John S Last edited by xxxJohnBoyxxx; 07-15-2011 at 03:47 PM. | | | 07-15-2011, 04:55 PM | #3 | Senior Member Join Date: Mar 2005 Location: Portland Or Posts: 2,666 | The TI was entry level so pretty much all of them have the manual heater control. What exactly is the problem? If its NO ac the most common failures are the Radiator Fan relay failing, or the pressure of the refrigerant in the ac system. Or Failed AC compressor clutch. If its no fan its the same silly relay/box. Cheers. Dave __________________ Dave - PDX 1995 318ti - Active Black and Tan. 2005 330xi - Mtech 1 - 6spd - Orient Blue/Black | | | 07-19-2011, 01:18 AM | #4 | Junior Member Join Date: Jul 2011 Location: Australia Posts: 12 | Heater/air con not working OK My bad for not writing up the full history... my car had a heart transplant a few months back, and ever since then both the heater and air con have not been working where they both had been previously. Hence my thinking that its most likely a wiring issue. First thing I did was check appropriate fuses: all good. Fan also works (blows ambient temperature air through the vents), so thats not the problem. Removed the electrical connection from the heater valve and used a multi-meter to check voltage of individual wires as well as voltage across the connector terminals when car was running and up to temp. The positive terminal/wire shows 12 volts but the neg terminal shows nothing and there's no volts across the connector terminals. I COULD check 100% that this is where the issue is by plumbing a dummy wire straight from the neg battery terminal to the connector and hooking it back up to the heater valve. If heat works, then the neg wire is the issue... but that doesn't explain lack of air con?? I suppose my plan for today is to trace the negative wire backwards manually, but I would have preferred to find out where it is connected to using wiring diagrams and/or other ppls knowledge. Presumably there is something electrical between the heater valve and the battery that the neg wire runs through. Anybody know what it is? From the wiring diagram and my limited mechanical knowledge of the heating system, it looks like: Battery ---> fuse ---> heater valve ---> blower motor ---> blower relay ---> Ignition?? NOTE: This is the first time I've tried using wiring diagrams for anything other than hooking up a stereo. I believe I may be wiring diagram illiterate. I had thought maybe there was something referred to on the wiring diagram as the "Temperature wheel switch" and I had thought that perhaps this was the temp dial on the dash... so I went looking on various threads until I found this: http://www.318ti.org/forum/showthrea...obs+new&page=2 I thought it might be a good idea to double check the bowden cable mentioned in this thread since it seemed like a fairly common problem, and seem to recall my heater wasn't as hot as I thought it should be when it was working previously (although I knew sorting this out wouldn't fix my electrical issue, of course). I pulled out my glovebox and went poking around, then realised that of course my BMW is right-hand drive, so I should be looking on the driver's side (D'oh!). So now my 318ti is missing a glove box, clock and head unit, and I am no closer to sorting any issues with my heater or air con. Joy! I'll post this somewhere more appropriate in the forums so that I might get more responses, but if you have any thoughts/suggestions, feel free to contribute | | | 07-19-2011, 02:55 AM | #6 | NOBODY F's with the Jesus Join Date: Oct 2006 Location: Ventura California Posts: 7,824 | You don't have to pretend to be a girl to get help around here | | | 07-19-2011, 03:55 AM | #7 | Junior Member Join Date: Jul 2011 Location: Australia Posts: 12 | Quote: Originally Posted by cooljess76 You don't have to pretend to be a girl to get help around here | *Sigh* Life would be so much easier if I was male. It sucks to admit it, but its true. Why do guys always assume I know NOTHING about cars simply based on my genetalia?? And then, why do guys feel so emasculated when I display that I know a reasonable amount, and occasionally know more than they do? My husband and I just purchased an F250 Custom to pull horse and car trailers (yay!). It needs rego, but we know from experience with previous cars that if I take it to get inspected it will get failed on a crapload of stupid small things (e.g. windscreen wipers that are slightly worn, oil seeping -not leaking- from around rocker cover gasket etc.). Then the kindly mechanic will hand me the report, tell me that I have an oil leak which could be detrimental to my car's engine and MUST be fixed before it can pass for rego. He'll offer to fix this for me, estimating that it will require 4 hours labor plus a new gasket that costs a LOT more than it should. Of course, the same might be said for men in business suits. For some reason mechanics think that a tidy, respectable business man is ripe for the ripping-off. Dunno why? If my husband takes it for rego, they probably won't even bother inspecting the bloody thing, and just hand over a fudged report and a fake brake test print-out (has happened multiple times in the past). I got very grumpy last night when we had this conversation... but in the end we agreed that it will save us time and money if my husband takes it. Lame!! The solution: next time I take a car for rego I'm gonna dress and act like an impoverished man and everything should be sweet. Now where's my wife-beater shirt? Any volunteers to hack my hair into a mullet and knock out a few of my teeth? | | | 07-19-2011, 09:17 PM | #8 | Member Join Date: Jun 2011 Location: monterey, ca Posts: 35 | did somebody say genitalia? and on a car forum? | | | 07-19-2011, 10:11 PM | #9 | Senior Member Join Date: Nov 2004 Location: Bremerhaven, Germany Posts: 977 | Quote: Originally Posted by Metalhorse The solution: next time I take a car for rego I'm gonna dress and act like an impoverished man and everything should be sweet. Now where's my wife-beater shirt? Any volunteers to hack my hair into a mullet and knock out a few of my teeth? | I might suggest donning work overalls and then while you are there ordering some parts. The ETK is online with enough detailed information to awe the average parts guy. You could accidentally transpose a couple digits on something and then help out a little with the search: "Oh, I bet that one's in subgroup 40...." Just a thought. | | | 07-20-2011, 01:02 AM | #10 | NOBODY F's with the Jesus Join Date: Oct 2006 Location: Ventura California Posts: 7,824 | You'd be suprised. I'm probably the roughest/ugliest dude on this forum. I've been to hell and it shows. Rarely do I take my car in for service or pay to have things done. I do almost all of my own work, but occasionally if I'm lazy or perhaps just don't have a particular tool, I'll take my car into a shop. As soon as they see the BMW roundel, they almost immediately start devising a plan to rip me off. Then, once they realize that I know more about my car than they do, they get attitudes and try to take their frustrations out with either sh!tty work or overpricing. Owning a BMW is a lot like being a woman. It doesn't matter if you walk in wearing greasy coveralls and steel toe boots or if you walk in wearing an evening gown and heels. As soon as they find out you own a Bimmer, they automatically assume that you know nothing about cars. Here's my professional opinion regarding your HVAC issues. You mentioned that your car recently underwent a "heart transplant". I'm assuming that the engine was replaced, correct me if I'm wrong. While it is possible to remove/install an engine without disconnecting and venting the A/C charge to the atmosphere, many/most people simply disconnect the pressurized lines from the A/C compressor allowing the system to dump all of it's pressure/charge instead of unbolting the A/C compressor from the engine and leaving the pressurized lines hooked up. Unless the system was leak checked and recharged after the engine was replaced, the system likely has little to no pressure in it. The A/C compressor, even if hooked up electrically and propelled by a belt, will not kick on if the charge pressure drops below a certain point. Next, the heater. Any time you open the cooling system loop ie; remove the radiator, hoses, thermostat, water pump, valves or fittings, it's imparative that you bleed the air out of the cooling system. 4cyl BMW's are prone to what's known as "vapor-lock" or air-lock due to placement of the radiator in relation to the routing of the cooling system flow. Since air travels up, it goes to the highest point and becomes trapped creating a void. Eventually, it makes it's way to the radiator which in turn prevents coolant from circulating through the engine and heater core. Usually this causes coolant to evaporate and pressure to build up and as a result, the engine often overheats. Some cases are worse than others and in some cases, cabin heat is lost while the engine is still capable of cooling itself. If little or no coolant is circulating through the heater core, you won't feel any heat coming from the vents. Most mechanics/shops don't know how to properly bleed the cooling system on 4cyl BMW's simply because they don't have as much experience due to 6 & 8cyl BMW's being far more common. So my recommendations are to recharge the A/C system to the proper pressure and have it leak checked. And properly bleed the cooling system following these instructions to the letter: http://www.318ti.org/forum/showthread.php?t=27983 | | | 07-20-2011, 02:57 AM | #11 | Senior Member Join Date: May 2011 Location: Michigan Posts: 183 | Don't you have to have a vacuum pump to void the a/c system before you refill it? Or can you just recharge it with new refrigerant. It seems like all my cars are having air problems this summer. | | | 07-20-2011, 03:01 AM | #12 | NOBODY F's with the Jesus Join Date: Oct 2006 Location: Ventura California Posts: 7,824 | Yeah, you need to suck the air out as refrigerant goes in, otherwise the system will have too much pressure and not enough refrigerant. | | | 07-20-2011, 03:03 AM | #13 | Senior Member Join Date: Mar 2005 Location: Portland Or Posts: 2,666 | Yes you need to use a vacume pump before charging if its been open to air. You also need a new dryer canister if its been cracked open. You also need a set of REAL gauges, the cheesy ones will just over or underfill the system. The real guages allow you to bleed charge into the can and put it back in the system. AC can be dangerous if you dont have the experience/training. Be careful It takes about 2 to 3 cans to fully recharge and balance the stock system by the time your done plus a lubricant charge. Dave __________________ Dave - PDX 1995 318ti - Active Black and Tan. 2005 330xi - Mtech 1 - 6spd - Orient Blue/Black | | | 07-20-2011, 03:08 AM | #14 | Junior Member Join Date: Jul 2011 Location: Australia Posts: 12 | @ cooljess: Yes "heart transplant" refers to an engine swap - sorry, one of the other forums I post on uses that term a lot. I did read about bleeding the cooling system when I was looking through the HVAC forum, but I presumed (perhaps wrongly??) that because there is no power to the negative connector to the heater valve when there should be, that air in the cooling system is not the primary issue. Even so, perhaps I should burp the system and check the bowden cable from the temp dial to the heater box is connected up correctly before worrying about the electrical issue. If these things don't fix the problem, plumb a dummy wire direct from the neg terminal on the battery to the heater valve and see if I can get heat from the cabin air vents. Thanks for your help @ john firestone: thanks for the suggestion. Overalls smeared with grease and diff oil should help - along with acting like I know everything BEFORE getting the inspection done. I do need new boot and bonnet struts, but I'll hardly impress anyone with that! I'll have to find some obscure and not-too-expensive part to order | | | 07-20-2011, 03:08 AM | #15 | Member Join Date: Jun 2011 Location: monterey, ca Posts: 35 | when i put the M42 in my E21 i experienced major air lock in the cooling system. took a while to figure out how to fix the problem, but what i have to do is remove the heater hose at the firewall and fill the radiator till it flows out of the heater hose. worked like a charm. | | | | 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 | | | |