ktr6

The blower motor in my 958 CTT has started to function intermittently. I have seen the DIY thread on pelican about the blower motor resistor repair on 955s and was curious if this same problem occurs on our 958s? Any help would be greatly appreciated.

deilenberger

There haven't been many reports on failures on the 958 - so it's a tossup which part will fix it. If you have access to a diagnostics tool, it's possible the motor controller has memory in it that will record failures. Or not.

2011_Cayenne_S

I replaced mine ... it's pretty easy.
I think you have to replace whole thing on 958.

ktr6

Heating and Air Conditioning - HVACModule Identification
Description BKE_VORNVIN WP1AC2A2XBLA81502Hardware Number 7P5907040LPart Number 7P5907040L Current Fault CodesU040100
Invalid Data Received From ECM/PCM "A" Factory Fault Code 33537
Warning Indicator Off
Test Completed This Monitoring Cycle
Test Not Failed Since Last Clear
Test Completed Since Last Clear
Not Pending DTC
Test Not Failed This Operation Cycle
Fault Passive

smegman

OMG me too! It only goes max power for a few seconds (mostly when using AC) but also happens when I turn on the defroster too... will only go max power for a second or so and then tail off to low power... how to fix this? I was unable to find threads on this issue, probably my poor google-fu

ktr6

I have had a little more time with the durametric today. Still pulling the same fault code as the one listed above even after clearing. One other observation is that I am unable to activate the defroster/blower using the durametric. I tested it on other systems and it appears to be working fine. My drain for the HVAC was clogged at one point and the passenger side floor was soaked (fixed now). Maybe the problem started there, will keep hunting.

smegman

I had water issue on the passenger side as well just before this issue started happening due to cracked ac drain pipe

, I took the car to the dealer and they replaced the blower motor under warranty which seems to have solved the issue

ktr6

Thank you for the input, going to replace the blower motor this weekend and see what happens. Hope it does the trick.

ktr6

Update. My new blower motor arrived last night and I managed to install today. Happy to report that my HVAC system is back up and running like it was before and the fault code the durametric was reading has cleared. The job itself was not that bad just required some research on what needed to be removed etc. Things I learned:

-Blower motor failures in earlier Cayennes seem to be quite common. It can either be due to a bad external resistor/regulator (which can be replaced) or the blower itself-good DIY on Pelican for the older model range. Failure is less common in 958s and our unit is all one piece (blower plus resistor).
-Cost for a new unit for the 958 ranges from mid 200s up to 500ish depending on brand and where you purchase. I found a genuine OEM unit for 320 with free shipping and pulled the trigger.
-While you are in there I would plan on replacing your cabin air filter and making sure your HVAC water drain tube isn't clogged as mine had been (I blew some compressed air through it). I was amazed at the amount of dirt on the filter-guessing mine had never been changed.

Here are the steps I took:
1) Remove the two passenger dash vents. I used two small flat head screwdrivers to release the tabs inside the vent. Shine a flashlight inside the vent and you will seem them. The vent near the door will require you to remove the plastic fuse cover and remove the two torx screws (T15 I think).
2) Open the glove box and remove the trim piece above the glove box door, I was able to do this by hand. Once the trim piece is gone you will see the Torx screws for the top of the glove box.
3) I then turned my attention to the plastic piece below the glove box. There is a single Torx screw to remove and it simply pulls down by hand. I went ahead and removed the electrical connections to the 120V adaptor and the footwell light to get it out of the way.
4) Remove the plastic footwell air distribution tube, you will now have access to your cabin air filter to change it out.
5) Back to glovebox, remove the screws that were under the dash trim piece (top of glovebox, along with two screws the bottom of the glovebox. Remove electrical connections. My glovebox came out as a unit after sliding it down and out.
7) At this point I went ahead and unclamped the rubber water drain hose that runs to the firewall from the AC unit. I had a gush of water fall into the cabin and blew some compressed air into the hose (towards the firewall) to try and clear it. I poured some water through and it drained our underneath the car so hoping that means my drain is open.
8) You should be able to see the blower motor at this point. Remove the main electrical connector to the front of the unit. Next if you look at the back towards the firewall you will see a red wire that runs along the back of the blower, simply pull it down and push it out of the way.
9) There is a metal bracket that is blocking the blower from being being unbolted and slid out but fear not as the blower drops down to the floor when being removed. If you look underneath you will see 8 screws in a vertical orientation. Remove these and save them. The unit should now pull downward and forward and can be removed. The blower itself mounts to a bottom cover/bracket, pull the old unit out and put your new blower in. Reinstall is the opposite of what you just did.

Plan on a couple of hours for the job, if you have basic DIY skills this is a very reasonable job. I hope this can help someone else in the future if they encounter a problem like I did. Good luck.

deilenberger

ktr6 - thanks for the clear write-up. I'll try and remember when I'm home to snip and copy your message to the Cayenne DIY forum.

jimva23666

Thanks for the write-up! Had a the same issue with an '11 CS I just bought. Your instructions were a big help! Like you said, couple hours. Not bad at all.

AGARubberDuck

Just got done replacing the blower unit following this write-up. I had the intention of snapping pics and augmenting the instructions, but it really doesn't need any help. Thank ktr6!

For those who come later (and possibly from a 955/957) Note that while it 'may' be possible to do this without taking out the glovebox (as it was on the 955), do yourself a favor and just pull the vents, trim and glovebox.
Tools needed:
Torx t-15, screw driver style is best. Used on the lower plastic panel (1), Right air vent (2) and glovebox (3 upper, 2 lower, 1 right side)
5.5mm socket on a screwdriver handle, (8 in the vertical orientation around the blower fan and cowl - cowl comes out as separate piece allows space for the fan to come out the bottom.)
Small flat-blade or pick for the air vents. - 5 on the middle vent, 2 or 3 on right vent along with the 2 screws. These clips are metal and spring loaded. Gently pry the hook toward the center of the vent while pulling the vent outward. (or youtoob it)

Easily the worst part is the 2 vertical screws on the right-most side. There is a large wire loom directly in the way, but you can get around it.

Again, thanks OP for this write up. - super simple to follow and very DIY.

Randyg308

don't know if this helps, my blower motor has failed twice,with in 1 year and 3 months, because of clogged drains (both ac and cowel) water in the passenger foot well etc, some what common on the 958,a very bad design,my car is a garaged vehicle, of course I use it and some debris will fall into the cowel area, but I'm not under any trees, or off roading etc and no way should it clog up that severely, especially since it was at the dealer 3 times with in that year, for different reasons (bolt recall, tow package install, door actuator replacement) it would have been nice if the dealer pro actively checked the drains when it was there, since number 1 my car had that issue months before and that its a known issue, and the service manager himself told me he sees this issue and its a poor design, you know they give a checklist when you pick the car up, that details the over health of the car, like brake and tire wear, fluids,ac performance etc, you know like they really care about you and the car, but no section for the drains? I cant find it but I believe there was even a service bulletin from Porsche to the dealers about the cowel drains, any way I'm obviously upset, all the dealer talks about is the quality of the service dept,the best of everything etc.my service guy couldn't be nicer, but really for $185.00 an hour its not acceptable, those 2 repairs for the drains by the way were pretty much identical, blower motor replacement, seats and carpeting removed and thoroughly dried etc, around $1800 each time,a lot of labor and time and 2 weeks at the dealer in my situation. stay on top of the maintenance of those drains, and possibly remove the cowel drain plugs as some have recommended as per the Porsche service bulletin I mentioned.p.s. my car had 12000 miles when this first happened and 19000 the second time.

deilenberger

Randy - as I mentioned in the PM to you.. I believe there is a TSB (Technical Service Bulletin) on the subject - but haven't actually seen it. Simple enough solution - remove the drain outlet seals or ask the dealer to. Problem solved. Probably. You still might want to take it in every year or so to have the drains checked. I can understand with Florida's daily thunderstorms the vehicle can see a lot of rain in a short time, but do you regularly park it somewhere that things like leaves, palm-fronds, etc might fall on it and be washed down into the cowl?

BTW - a few sentence/paragraph breaks mebbe?

Randyg308