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Heater blower motor - high speed only??

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ossingersnw

Heater blower motor - high speed only??

Post by ossingersnw » Wed Oct 12, 2011 2:29 pm

The blower control in my '85 635CSI is functioning in Off or High - Only! I remeber that there is a blower motor resistor or control unit somewhere, but can't remeber where? Anyone know what could be at fault here?

Mark

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Please post your question . . .

Post by GRNSHRK » Wed Oct 12, 2011 3:30 pm

...in the correct forum #-o

This would belong in the "Engine-Mechanical-Electrical" section :-?

As far as your question is concerned, the blower motor transistor (not resistor) is located behind the blower squirrel cage itself. For the A/C, that's up under the hood, black sheetmetal cover by the windshield wiper system. I think the heater blower is buried behind the dash somewhere, and more difficult to access :-k

Common problem, good luck 8)

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ossingersnw

Post by ossingersnw » Wed Oct 12, 2011 3:43 pm

Opps your right, posted to wrong place.... Thanks for picking this up though, and Yes! the transistor is what i was trying to recall! Will dig into that this week and get if fixed.

Thanks again,

Mark

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Post by Chris Wright » Thu Oct 13, 2011 2:11 am

ossingersnw wrote:Opps your right, posted to wrong place.... Thanks for picking this up though, and Yes! the transistor is what i was trying to recall! Will dig into that this week and get if fixed.

Thanks again,

Mark
Here is a troubleshooting link:

Heater or A/C Only Runs on High - Troubleshooting:
viewtopic.php?t=14791&

Here is removing the heater blower and replacing the heater blower transistor (with lots of pics!):
http://www.normgrills.net/bcg/Blower_Transistor.htm
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Tim

Read thru your blower transistor replacement...

Post by Tim » Sun Feb 12, 2012 9:35 pm

I looked thru all the pictures and am wondering when you get to the board has the transistor that needs replacing - I would think that you would or could buy the whole board with a new transistor and avoid having to solder and cut the rivets off. Do you know if you can buy the whole thing? Probably a whole lot cheaper to replace the transistor I'm sure but for those of us that are rivet and solder challenged....you know?

Just wondering - sounds like something that eventually plagues all 635s - is that a fair statement. How many miles did you have on yours? Just curious if this is mileage driven or just time driven or maybe both.

Thanks - I'm a hopeful soon to be new owner...

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Re: Read thru your blower transistor replacement...

Post by Chris Wright » Mon Feb 13, 2012 4:23 am

Tim wrote: I would think that you would or could buy the whole board with a new transistor and avoid having to solder and cut the rivets off. Do you know if you can buy the whole thing? Probably a whole lot cheaper to replace the transistor I'm sure but for those of us that are rivet and solder challenged....you know?
Yes, they have the transistor board for $70 ...... Hmmm .... $2.95 for the transistor from RS or $70 for the assembled one, good motivation for leaning how to solder. :mrgreen:

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Tim

Re: Read thru your blower transistor replacement...

Post by Tim » Mon Feb 13, 2012 7:17 pm

Chris Wright wrote:
Tim wrote: I would think that you would or could buy the whole board with a new transistor and avoid having to solder and cut the rivets off. Do you know if you can buy the whole thing? Probably a whole lot cheaper to replace the transistor I'm sure but for those of us that are rivet and solder challenged....you know?
Yes, they have the transistor board for $70 ...... Hmmm .... $2.95 for the transistor from RS or $70 for the assembled one, good motivation for leaning how to solder. :mrgreen:

Image
Chris, of course you are right but for those of us that are challenged in that area and do not have the equipment the 70 buck route isn't a bad one and then there is my time involved with learning- getting a good grinding tool, soldering iron - etc. and I'm getting tired just thinking about it. It's like the thread on taking out the instrument cluster and replacing the gears on the odometer - wow - I can just imagine if I was the ham fist that dropped the cluster - oh heck - that would be so oooooo expensive.

So although I agree with you in theory - the practicality of this for someone like me is not there - a $70 dollar unit is pretty easy going, albeit expensive.

Now I have another question of you - your name has come up in another discussion I am entering into about the AC and getting it going in the car. I have talked with my Bimmer mechanic - and they of course only use OEM parts so they can warranty the work - while I can appreciate that it is not the most economical way to go, that is if it is a simple compressor or what if it's an evaporator which requires the dash to come out and it's not the compressor at all? Well you can see where that conversation was going - well to me down a very expensive road potentially.

So you were mentioned as a person that had a thread about AC work - and replacing stuff with other than OEM and then there is R12 and many still have some or can still get it - something like that. I believe I can still get some from a cheap sourse. So I'm trying to figure out what to do? Can you point me to a thread that would be helpful?

Thanks so much for the help for a newbie,

Tim
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Post by Carlp336 » Mon May 14, 2012 8:58 pm

i did this for 2$ never having done it before.. cheaper than 70.

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Tim

Post by Tim » Fri May 18, 2012 6:03 pm

Just a brief update to the dilema of the fan on either on high or off deal. There are two things that can affect this - the transistor board pictured here and resistor replacement and one thing not mentioned - the switch itself.

I replaced the board you see here - actually that was done by the previous owner as part of the deal or me buying the car. So I didn't really care if he soddered or bought a new one - he chose to buy the new one. Still that didn't fix the problem. I have just gotten that taken care of - secret - new switch. Mechanic told me they hardly ever go bad - well mine did. Now you might ask - what is the cost of a new switch OEM type that is - about $200 bucks. My mechanic had a test unit he sold me for $75 - it worked and it works now and so do all the things on my car now.

It was also a long and tedious job - mechanic charged me 2 1/2 hours labor - 1 1/2 hour labor for adjusting the valves and replacing the banjo bolts with a locktite variety. Said that he only charged me 2 1/2 hours but that it took him longer than that - also replaced some bulbs in there at the same time. I have a particularly thorough and good "wrench".

Now I picked the car up yesterday and it was at closing time - he left and locked up and I left - well the blinkers didn't work.....oh hell. Had to take it back in this morning - what was it you might ask - well when reconnecting the hazard light/button he put the plug in upside down - told me on the phone when I called about it that there was only one way to put the plug on - well he found out that you can indeed put the plug on the hazard light upside down - all these years he had been "lucking" out putting the plug in right. Funny - he learned something - he also becuase of that fixed one of my high beam headlights for free - nice.

Now I am ready to truck off to the Vintage in Winston Salem next weekend. Hope to see some of you there. Look for a burgundy metalic with Llama beige interior - looking very nice I might add- shark. I'll be looking for all you others there. My buddy Roy will be there and I'm looking forward to meeting him!

Adios - hope this helps others with a fan switch problem! Happy motoring!

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Post by GazM3 » Fri May 18, 2012 10:23 pm

Just wanna confirm the a/c fan is the one in the engine bay and the heater fan is buried in behind the dash. ??
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Post by Chris Wright » Sat May 19, 2012 3:30 am

GazM3 wrote:Just wanna confirm the a/c fan is the one in the engine bay and the heater fan is buried in behind the dash. ??
Nope, the other way around. The heater fan (Ref #6) is in the engine bay, the A/C fan (Ref #5) is in the console.


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Post by Chris Wright » Sat May 19, 2012 3:42 am

Tim wrote:Just a brief update to the dilemma of the fan on either on high or off deal. There are two things that can affect this - the transistor board pictured here and resistor replacement and one thing not mentioned - the switch itself.


Glad you got it all sorted out! 8)

But Actually, it was mentioned. The link above takes you step-by-step through the troubleshooting to tell if the problem is one or both of the blower transistors or if it is the transistor or "pot" in in the switch in the console. This is the link on that page that shows how to rebuild the switch in the console:

Here is replacing the transistor in the blower control in the dash:
viewtopic.php?t=2465
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Post by GripGreg » Sat May 19, 2012 4:08 am

Tim; here are a coupla tips for you.
#1-For the R12 replacement check out 'super-freeze.com'. It looks real good. They say it's phase 2 of the R12 replacement. R134A being phase 1. And they say they've had complaints about it being too cold! I'd rather that than the other way!
Notice the hyphen? I went to India w/o out it. You want Meterie, Louisiana.
#2-Also, about your a/c compressor, check out; A.P.E.. I spoke to Tony @
817)624-1100.
The Post Office will send up to 70lbs. if it fits their largest box for $15!!!
Anywhere in the lower Continental U. S.! As in Fort Worth, Texas!! C'MON!?
I think I heard from John in Simi that a compressor rebuilt in SoCal will cost at least $500 by itself! Then you should get your hoses re-built by taking them to a reputable hose manufacturer to ask them to re-place the hoses using the end connectors you take to them 'cause I doubt they're around anymore.
I'm checking my compressor right now & if needed, guess where I'm goin'.
Oh, yeah, go to where they work on big rigs to ask about a good hose manufacturer. They should know, shouldn't they? :-k
Good luck,,,,Greg (back under my small shade tree)
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Post by GripGreg » Sun May 20, 2012 3:59 am

Yeah, that's the one. Where was it hidden? That's a rhetorical question.
I'm glad it was posted somewhere. Makes me feel better 'cause it wasn't lost.
Hit the apex
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Tim

Post by Tim » Mon May 21, 2012 3:14 am

Hey Chris,

You're right and I saw this way back. I am always impressed at the lengths some will go to in figuring how to get into a switch or a board and solder and replace pieces. This last link you sent I just went thru again - that was painful. This guy finally figured it out - didn't tell you exactly how much he spent going from one thing to another before he finally got it worked out. Geez it tired me out just reading thru it - I can't imagine that was worth all that. I bought a test switch for 75 bucks and this guy spent 40 pounds on one fix that didn't work - I can understand persevering but this goes a little beyond what I would think most would attempt. My time and nerves are worth saving to me - to others this might work - not me.

I appreciate it but would never, ever attempt it and I'm not sure if this guy that wrote this solution would if he had it to do over - but some like, no love the challenge - me I have more important things to do like waxing my car or better still driving it.

By rhe way have I told you guys how much I love driving my new to me 6 - it is a joy - a total joy. The big issue was, to digress back to the switch- putting the damn thing in - worrrying with the cables that attach to the slide pods. It took my mechanic, who by the way has been working on bimmers for 40 years, about 4.5 hours to put the thing in - now I'm not familiar - how long do you think it would have taken me. He charged me 2.5 hours - nice of him I thought - so I guess I'd still be working on the damn switch if I had been reading these instructions and trying to get the switch back in. Geez - not for me - there are some jobs I'll tackle but man this ain't one of em. No sir. I'll leave this to you other guys.

My advice to most that aren't one of the "brave few" is to pay for a new switch and have an expert put it in and be back in the drivers seat in a day. I like that option.

Now to the AC system in general. I converted to R134A = maybe not the best idea but it works and it works fine really. I had an absolute pile of work performed to my car. I can hardly remember everything - power booster loomed large and the bill for that fit the term large. Had the valves adjusted and after all this time of it sitting for 3 or 4 years total at least before they were adjusted only 2 valves were out 2000ths - pretty damn amazing I'd say. Had the banjo bolts replaced with the locktite bolts. Had hoses replaced, had idler arm replaced, other bushings, front shocks needed replacing - but rears were fine. Again amazing - bilstiens really are great shocks. Rebuilt the compressor. Those are the big highlights Oh forgot to mention the master and slave clutch cylinder.

I replaced the steering wheel that had a hole in the leather and the rest of it was cracked - the leather that is - got one for 200 including shipping and I sourced a really nice wooden shift knob and the guy was really nice and got the insert for the right dogleg pattern and put it in. Nigel 0ver in England. Great guy by the way - others may have heard of him - something like Nigel motorsports. Now my switch works great - AC works great, car feels great. Oh my wrench also reglued my original headliner back on the sunroof. I had a replacement but the original is much nicer material even if a bit old but worth preserving imho. Then to top it all off I took the old blaupunct out and replaced the speakers and stereo with new modern stuff - kenwood hd that has more gadgets that I can begin to understand - but slowly but surely I will make it work for me - it's got blue tooth, remote, mp3 etc. and great speakers. Sounds great.

I have now put as much in the car as I did to purchase it; no more I think. Got a car cover too. Anyway - I've had offers to sell but have passed them up. One guy offered me 20k - I should have asked to see the money....lol. But I didn't - it's just too nice now, but I gave him my number just in case. At this point I love the car and really plan to keep it for a long time. I say that about other cars I've had but this one is different. It just has so much going for it - looks so nice and it has a lot of room.

I hope to see you guys up in Winston Salem next week. I'll be going and it will be a super joy driving the car now that it is really sorted. Thanks for all the advice. I now have one more thing to do - get my seat back pistons replaced. I plan to tackle this one. Hope I am up to the task. Had some good advice.

Sorry to be so long winded - I need to post pics. It's a burgundy metalic with Llama beige 85 Euro. See you all there in NC hopefully. I'll be parked in town and will participate in the ralley. I am ceriifiably car crazy to spend so much on this car but I think it is worth it. What other cars can you drive for 16k that look as good or are as much fun to drive. I guess it depends on each one of us to figure that out for him or herself.

Tim




Chris Wright wrote:
Tim wrote:Just a brief update to the dilemma of the fan on either on high or off deal. There are two things that can affect this - the transistor board pictured here and resistor replacement and one thing not mentioned - the switch itself.


Glad you got it all sorted out! 8)

But Actually, it was mentioned. The link above takes you step-by-step through the troubleshooting to tell if the problem is one or both of the blower transistors or if it is the transistor or "pot" in in the switch in the console. This is the link on that page that shows how to rebuild the switch in the console:

Here is replacing the transistor in the blower control in the dash:
viewtopic.php?t=2465

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Re: Heater blower motor - high speed only??

Post by ilouie » Tue Oct 24, 2017 10:26 pm

This post seems a little old, but it's a constant battle with this issue. Would anyone know how many ohms is the resistor?. The little color coded one?. TY

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Re: Heater blower motor - high speed only??

Post by baders » Wed Oct 25, 2017 12:20 am

A bit hard to see, but it looks like brown, black, red. Which would make it a 1K ohm resistor.
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