I've been having trouble with my heater since I bought my 2002 S40 a few weeks ago. The heater keeps changing speed regardless of what manual setting I use. I read previously that it could be the blower motor resistor. After taking it to the dealer's mechanic twice (the first time they said there was nothing wrong, and then I brought it back again after it continued to act up), they told me today that it isn't the blower motor resistor, they said it's the heater control module. They said that if they ordered it new it would cost $600! Does this sound at all right?

They said they will see about finding a used module and will be in touch with the dealer about this. Does this sound likely that this is what could be wrong? The heat blows very hot but like I said the speed is all over the place as if I'm constantly switching speeds but I'm not. It can get quite loud as if I'm switching it to high back and forth. The mechanic said today that even tapping the **** causes it to spike, which it does, and he seemed certain that was the problem. If the dealer won't cover this, I don't know how I'm supposed to pay for this because that's a ton of money I don't have after buying the car just weeks ago.

 

I've been ripped off by a dealer once too often. Years ago I had a dealer tell me my no start condition was the computer. They replaced it for $500 only to discover it was the fuel pump! I say run away from them.

You can actually fix the blower resistor with a $3 Radio Shack part. Transistor 2N3055 NPN. You remove the heat sink that it's mounted to under the pax side glove box, remove the transistor, mount the new one and solder it to the old wires. Mine has been working for over a year now.

As for the heater control module, my local pull-a-part prices this kind of part in the $15 range. If you are near Knoxville there is a nice 2000 model with most of the center console intact. Have anything like that where you are?

Transistor


Blower motor resistor with heat sink

 

The only problem is I have to take it to the mechanic they tell me to in order for them to cover their 50% of the repair as part of their 30-day warranty. So I have no choice but to go where they tell me to.

I do know about the transistor but I'm not comfortable doing it myself. I mentioned the transistor/blower motor resistor to the repair center (twice), and they insist it's the heater control module.

There's a thread here:

https://volvoforums.com/forum/volvo-...randomly-1101/

where somebody else had the same exact issue. They refer to something called a "Electronic Blower Speed Power Module". I looked it up on Google and couldn't even get any hits other than this thread. My 2002 S40 has the automatic climate control system. Now I don't know what to think.

They called me today and said they're getting a used part, but didn't give me any idea yet on what that will cost. The dealer will cover 50% parts and labor.

I just don't want those idiots to replace something expensive if it's not necessary. Any thoughts on this?

 

That is why I suggested the transistor fix first. It's cheap and fairly quick so you can tell right away if you need to look at other more expensive parts. However, if you must pay for someone else to do the repair it can quickly become expensive too. Is there a neighbor with a soldering gun in need of a beer?

Whatever the outcome please let us know the fix so we can help others in the future with your same symptoms.

 

According to a post I found on tamparacing.com, this part known as the "climate control module" is indeed extremely expensive and notorious for failing. Here's the relevant part of the post:

"A customer thought he had a bad CCM in his 2002 Volvo S40, so he brought me one to install for him. Didn't fix it. So he brought me another one. Same problem. Long story short, he had a bad connection at the relay board, and I now have two used, but good CCM's at the shop. According to the guys at Volvo of Tampa, these modules are notorious for going bad, and they're about $900 new (or about $200 at any salvage yard....if you can find one)"

So if it is indeed the climate control module (the mechanic called it the heater control module - must be the same thing I'm assuming since I have automatic climate control on my car) then he's not lying when he says it's around $600 new. The poster also mentioned that there are different "climate control modules" that were made available over the years for the S40, and what you need depends on what options you have installed:

"the difference is in the year of the car, Heated Seats (or not), and DSA (Stability Control)"

I have both heated seats and DSA, so maybe I should call the mechanic and make sure that he's getting the right part for the right version of my car. I hate leaving it up to them - I'd much rather take it to somebody who knows more about Volvos, but this is the only way I can get the dealer to split the costs with me. So I have to play it their way.

 

Our indy mechanic in Washington DC installed this (I believe) for $600 about two years ago when my wife's 2001 S40 exhibited erratic behavior, fan fast slow fast slow, cooling on and off. He had to have it programmed at the Volvo dealer around the corner, so is it the same module?

Anyway, the A/C is still not working correctly. I have the old module, it would be great if it could be tested to see whether it really needed to be replaced.

Does the S40 have something like a "final stage resistor"? That is known to fail on the BMW 5-Series 1999-2003 and causes the same behavior.

Any tips on what to look fornow would be appreciated,

Thanks,
-stephen
2001 S40

 

The 2000-2004 S40 has the infamous blower motor resistor above. This has failed 3 times on my 2001. Never has the CCM failed. Just my .02

 

Hudini,
I have the resistor prolem I think. I need to know where it is located and how to get it replaced. I know what the part looks like now but have no idea how to access it. Any DIY videos on the repair? Or any step 1, step 2, etc...? That would be really cool for a weekend fix that would make a world of difference for us newbies. I have never done this repair, and hopefully will not become an expert.

 

It's located behind the pax side glove box inside the ducting for the cabin air. The cabin air filter is right there too. Going from memory I had to remove the glove box and the felt/cardboard kick panel down by your feet. Then I drilled a hole in the metal support beam so my phillips head screw driver could access the top screw on the resistor. (Not sure if you could just remove the metal support beam) Once the electrical connector and screws are off then you have to wiggle it free from behind the metal support beam. The hole I drilled is covered by the glove box so that was not an issue.

The Radio Shack resistor above is quite fragile. It's a good temp fix but it's not up to automotive standards. You need a much heavier duty one (which are available through DigiKey) for a better fix. Or just buy a whole new resistor from Volvo.

 

I've had this issue since I bought my car used last October. I've been told for over a year by the dealer (not a Volvo dealer) that they would pay half of the repair costs, but they say they can't locate the heater control module. I had the car checked out by a local Volvo dealer/repair facility (very reliable) and they told me that the unit is shot and the transistor is not the issue, and that the entire unit needs replacing. I have another guy that was helping out with some repairs who is also very knowledgeable with Volvos and he said the same thing - he said if it was the just the resistor, it would either be on or off, but since the fan speeds jump all over the place, it is the entire unit that needs replacing. He also has been looking for several months in junk dealers and said he can't locate a unit that would match the one in my car (with the full climate control and heated seats and stability control).

At this point I don't know what to do. I need this thing fixed and it seems nobody can find a working unit except Volvo which I just can't afford. Any ideas? Should this unit be this difficult to locate? I keep getting told these things fail often and it's hard to find a replacement. I never would have bought this car if I knew about this, but when I bought the car (not from a Volvo dealer) I was told everything was okay - I even had it checked out before I bought it. Apparently they didn't check the climate control system.

 

Could someone please post a photo and/or part number of the "heater control module"? I'd like to know whether what I have is what we're talking about.

Thanks,

 

Have a look at this post regarding CCM for S40 or V40.
This is what controls your air con,heater and fan speeds.

Dash Bulb Replacement 01-04 S40/V40 - Volvo Owners Club Forum

 

i have the same issue, and i actually asked the previous owner, if they had it checked. He said, the dealer in Elk grove village il, told them $1200 for the whole unit. I ve also checked 4 different parting out s40 vehicles with the heated seats, and the dsa, and they all had the same problem. Then i decided to go and check out a volvo v40 at the volvo dealer, and it end up having the problem as well, so i ask the salesman, if it can be fixed, he said, of course after you buy the car. So i just learned to live with it, what else can you do

 

My 2003 S40 was having this problem until tonight Blower would randomly change speeds unless the dial was set to AUT or maxed out at 5. Very annoying. While doing research on this problem I read that the dials are controlled by potentiometers (pots). Which led me to try a product called Deoxit D5, its an electrical component cleaner. $12 a can at radio shack. After removing my climate control unit and pulling the circuit board out I just sprayed each pot front and back with deoxit and used a small flat head screwdriver to rotate each one back and forth for a minute. Put it all back together and the blower control behaves itself now. What a relief!

So before messing with the transistor behind the glove box, trying to re-solder something or paying $$$ to replace the whole thing, I recommend trying this.


...
I need to vent a bit. Why the heck did use Volvo pots for these controls? Pots are used where infinitely variable speed control, or volume or whatever is needed. Volvo used these on ***** that have defined selections; AUT,0,1,2,3,4,5. To me its just another example of Volvo over engineering something simple.

 

That is good information. Thank you.

 

Rapidly spinning the ***** to "clean" the contacts did not help. I also tried spraying some electrical contact cleaner on/in the three potentiometers, but I'm not sure it actually reached inside; they're pretty well sealed up. At any rate, that didn't help, either. With further reading, though, I found this diagram: Could one of these sensors be responsible? Has anyone tested or swapped any of these parts? How could they be eliminated from consideration? Thx, -stephen