# Climate control on '98 540



## carnut (Feb 26, 2005)

I hope someone out there can help me with this problem. I just purchased the 540 last week and after 3-4 days of driving, all the functions for my climate control have stopped working. What happens is every time I push the Auto button, it appears for about 5 seconds, with both 
temperature settings for driver and passenger set at 70 degrees F, and the fan setting is almost off. After this 5 second display, the entire screen turns off. I do feel some air blowing lightly through the vents, alternating between cool and warm. No matter what I do, I cannot get the display to stay on and make any adjustments at all, in fact, even if I press the Auto button. sometimes it will not even come on at all. If I press the manual button settings for the feet, dash vents or defroster vents, the display will do the same thing. I've searched the forum in vain for anyone else who may have had a similar experience, but no luck. Any ideas? Thanks in advance.


----------



## Ågent99 (Jan 7, 2002)

This sounds like the Final Stage Resistor acting up. Do a search here on those words...the part isn't too bad and installing isn't too bad if you are half-way mechanically minded. Check the DIY section here, too.


----------



## carnut (Feb 26, 2005)

Agent 99,

Thanks. I wasn't sure if it was the FSR as the symptons did not mirror any of the threads I searched for in the archives that were previously posted. However, today when I was driving to work, I got the fan on/fan off syndrome that I've read before. I'll go with the FSR replacement. BTW, I am very mechanically sound, so most of the DIY things I've read are well within my skill level. I'll post the results for archive purposes in the event another forum member has this problem. One other question, is the FSR a dealer only item. or should I go to the local parts store?

Thanks again!


----------



## Ågent99 (Jan 7, 2002)

Dealer only...if you have time to order and wait, try www.pacificbmw.com. They'll normally have the lowest prices. Pick up some extra filters (air, oil, micro) while you are at it.


----------



## carnut (Feb 26, 2005)

Agent 99,

Thanks. I'll check them out. I'll post the results on the outcome.


----------



## carnut (Feb 26, 2005)

Agent 99 and anyone else, 

Well, I replaced the Final Stage Resistor and it did not solve my problem. The only way I can keep the climate control on or working is by pressing and holding any of the three manual buttons that direct the cooling/heating to the feet, body, or defroster. If I release any one of those buttons, the display will turn off within 2-3 seconds, max. The fan also pulsates on and off in the car, never varying speeds, as if it were breathing. Also, none of the 4 buttons located on the far right of the climate control unit that operate the recirclulating air, rear window defrost, front window defrost, or AC even activate or work, but that was pre-existing before I picked up the FSR, I forgot to mention that originally. When I picked up the FSR from the dealer, he mentioned that they have made changes on the newer FSR unit. When I compared the two side-by-side, the major difference was that the new unit had many more "spires" then the old unit. The spires were also thinner in diameter then the old FSR. Any idea if they provided me with the wrong unit?

On top of that, on the way home from the dealership, I got the dreaded "Service Engine Soon" light. I plugged in the Peake diagnostic tool and the codebook informed me that it was "Catalyst Efficiency Cyl 1-4" What does that mean? 

HELP!!!!!!!


----------



## Ågent99 (Jan 7, 2002)

Going nuts with this car?? :rofl: sorry, couldn't resist.... 

Well, this is beyond my web diagnosing skills but now it sounds like an O2 sensor (which handles 4 cylinders...that is why you have 2 of them) may be headed out.

You need to visit a dealer and have them diagnose. If you can find a good independent mechanic, they are usually cheaper. There is a guy on here, M.Wong, who lives in Seattle and is very active on the board...he might be able to steer you some help.

Good luck!


----------



## carnut (Feb 26, 2005)

Agent 99, 

Thanks. Yes, I'm going a little nuts. No worries though, yet, I think.......

Re: the climate control; I am at the point of calling an indy shop and see what information they can share with me.

As for the SES light, I am going to reset the SES light and see if it reappears. If it does, it may be the O2 sensors or that catalytic converter (Forum search turned up that gem). If it's the cat(s) another thread mentioned going with aftermarket cats (Magnaflow or Carsound) which will be far, far less then the actual OEM replacements. 

Calling M. Wong, calling M. Wong, where are you? I live in your area, can you assist me or point me to someone who can? HELP!!! 

Thanks.


----------



## Ågent99 (Jan 7, 2002)

Send M.Wong a PM/email or he may see your cry and respond here. Be sure to not put a space in his handle: M.Wong (no space)


----------



## carnut (Feb 26, 2005)

WOW! I got the bad news from my indy repair shop. Approximately $900.00 - $1000.00 to replace the climate control unit. I seems that the part will be in the $650.00, and the labor to install and program the untit will be another $100.00. The remainder of the bill was to do a diagnosis on why the Service Engine Soon light came on. I used my Peake Research code reader and found a code that did not provide much detail (Listed in my original thread), they could not find a fault like that on my car, but they found some other codes that were related to the battery dying, and from the climate control unit itself. I asked the shop if I could look for a new control unit myself for less then what they quoted me and they informed me that they would not install other suppliers parts. Looks like a long and depressing weekend. I hope this isn't the beginning of a bad experience with this car, I've had it for all of 2 weeks.


----------



## chivas (Aug 31, 2002)

EBAYYYYYYY dot com....

you'll find one there and there.. 
try this place first:
http://usedbmwparts.com/

ask them if they have a unit for sale. good luck.


----------



## carnut (Feb 26, 2005)

Well, the problem is that the shop I am having it worked on *will not* install parts that they do not supply themselves. I could buy a climate control unit from a dealer or on ebay, but I would still need to program the new unit to make it compatible with my car. I KNOW that I can get a climate control unit cheaper and install it myself, but it will not work if it is not programmed to work with my cars CPU. I have to come to accept this unfortunate turn of events and hope that I don't have too many pricey problems like this in the near future. BTW, I still love the car!!!!


----------



## antgli (Feb 7, 2005)

carnut said:


> Well, the problem is that the shop I am having it worked on *will not* install parts that they do not supply themselves. I could buy a climate control unit from a dealer or on ebay, but I would still need to program the new unit to make it compatible with my car. I KNOW that I can get a climate control unit cheaper and install it myself, but it will not work if it is not programmed to work with my cars CPU. I have to come to accept this unfortunate turn of events and hope that I don't have too many pricey problems like this in the near future. BTW, I still love the car!!!!


carnut...sorry to hear about your unfortunate events. :thumbdwn: I hope everything works out for you. I just bought a 97 540 earlier this year and knew this car was a high maintenance car. So far I've replaced the waterpump. The radiator's my next preventive maintenance replacement along with hoses. Despite the high maintenance of the E39, it's still a great driving car! Anyway, let us know how your misfortunes turn out.


----------



## carnut (Feb 26, 2005)

antgli,

I'm picking up my pride and joy today. The techs working on it found no codes stored in the brain of the car to indicate why the Service Engine Soon light came on, just codes related to the battery being disconnected (By me) and abnormal battery drain, due to the failing of the climate control unit itself. They cleared out the codes for me, so I guess I'm out of the woods for now. I can hardly wait to get the car back!!! I'll follow this thread up when I get the car back.


----------

