HVAC Blower (Only) Acting Erratically
06-28-2014, 12:16 AM
#31
Rennlist Member
Looks ;like they can be had for less then $250
http://www.ebay.com/itm/New-Porsche-...-/200689107560
New! Porsche BLOWER RESISTOR (911 Boxster Cayman Carrera) oem VALEO 1059.4005
or 996.573.923.00 $179
http://www.ebay.com/itm/New-Porsche-...-/200689107560
New! Porsche BLOWER RESISTOR (911 Boxster Cayman Carrera) oem VALEO 1059.4005
or 996.573.923.00 $179
06-28-2014, 12:17 AM
#32
Ok, have you run a/c diagnostic? https://rennlist.com/forums/7057458-post5.html
Seems like the blower "resistor" (let's call it the driver) is the same as the VW part 1J0907521
http://www.ecstuning.com/Search/SiteSearch/1J0907521/
Still not cheap. The reason I suspect the driver is because the blower fan gets its positive power as long as the ignition switch is ON. The CCU signals the driver to ground the blower fan to turn it ON. When you turn OFF the CCU, there will be no control signal applied to the driver so it should not turn ON the fan. However, if the driver is leaking electricity, it could ground the fan and turn it ON. But once you remove the key from the ignition, you cut the positive power to the fan so it stops.
Seems like the blower "resistor" (let's call it the driver) is the same as the VW part 1J0907521
http://www.ecstuning.com/Search/SiteSearch/1J0907521/
Still not cheap. The reason I suspect the driver is because the blower fan gets its positive power as long as the ignition switch is ON. The CCU signals the driver to ground the blower fan to turn it ON. When you turn OFF the CCU, there will be no control signal applied to the driver so it should not turn ON the fan. However, if the driver is leaking electricity, it could ground the fan and turn it ON. But once you remove the key from the ignition, you cut the positive power to the fan so it stops.
Last edited by Ahsai; 06-28-2014 at 12:36 AM.
06-28-2014, 08:49 PM
#35
Instructor
Thread Starter
Join Date: Jul 2002
Location: Morgantown, WV
Posts: 142
Likes: 0
Received 0 Likes
on
0 Posts
Thanks guys,
I've got one on the way.
Now to start figuring out how to pull the center counsel out.
For $24.00 i would be a fool to pass it up or end up buying a $250.00 resistor. Even if it is not the issue (I hope it is).
I've got one on the way.
Now to start figuring out how to pull the center counsel out.
For $24.00 i would be a fool to pass it up or end up buying a $250.00 resistor. Even if it is not the issue (I hope it is).
07-01-2014, 10:23 PM
#37
Instructor
Thread Starter
Join Date: Jul 2002
Location: Morgantown, WV
Posts: 142
Likes: 0
Received 0 Likes
on
0 Posts
Update;
Got the correct switch and installed but somewhere between outing the car back together the immobilizer set itself.
I ran Durametric and got fault "25 W Lead".
What does this mean? I have power to the car but will not crank. Is there a reset I can do? Or am I stuck Gavin to get the dealer to reset the car for me.
I don't know what I did to set the immobilizer to active. I did remove the driver seat for better access under the dash. Could that have set the immobilizer?
Thanks.
Looks like trying to save a few hundred bucks turned into breaking about even.
Got the correct switch and installed but somewhere between outing the car back together the immobilizer set itself.
I ran Durametric and got fault "25 W Lead".
What does this mean? I have power to the car but will not crank. Is there a reset I can do? Or am I stuck Gavin to get the dealer to reset the car for me.
I don't know what I did to set the immobilizer to active. I did remove the driver seat for better access under the dash. Could that have set the immobilizer?
Thanks.
Looks like trying to save a few hundred bucks turned into breaking about even.
07-16-2014, 04:22 PM
#39
Update;
Got the correct switch and installed but somewhere between outing the car back together the immobilizer set itself.
I ran Durametric and got fault "25 W Lead".
What does this mean? I have power to the car but will not crank. Is there a reset I can do? Or am I stuck Gavin to get the dealer to reset the car for me.
I don't know what I did to set the immobilizer to active. I did remove the driver seat for better access under the dash. Could that have set the immobilizer?
Thanks.
Looks like trying to save a few hundred bucks turned into breaking about even.
Got the correct switch and installed but somewhere between outing the car back together the immobilizer set itself.
I ran Durametric and got fault "25 W Lead".
What does this mean? I have power to the car but will not crank. Is there a reset I can do? Or am I stuck Gavin to get the dealer to reset the car for me.
I don't know what I did to set the immobilizer to active. I did remove the driver seat for better access under the dash. Could that have set the immobilizer?
Thanks.
Looks like trying to save a few hundred bucks turned into breaking about even.
http://www.renntech.org/forums/topic...9114/?p=199180
07-16-2014, 11:44 PM
#40
Instructor
Thread Starter
Join Date: Jul 2002
Location: Morgantown, WV
Posts: 142
Likes: 0
Received 0 Likes
on
0 Posts
Update:
Sorry it has taken me a while to get back.
Good news. I did not need to have the car towed to my nearest dealer, Sewickley. I called them and was told that the immobilizer was not the issue of the "no crank" and that the immobilizer will not wipe codes in the car. I described the issue and was told to try and push the ignition switch in another 1/8". Sure enough it worked, it just wasn't engaged enough.
So, back to the issue at hand. It turns out it is not the resistor, check that one off the list. Second attempt. I bought a used blower off a salvaged 2001 Carrera with 21,000 miles on it for $54.00. Just installed it this evening and it runs consistent now, but only on the high speed setting. It physically does not run at full speed. And will stop running at roughly 3/4 on the CCU.
I think i've exhausted my options except for the most expensive and I think it might be the issue.
I ran across an article in Rennlist about a 986 where the same symptoms were happening. The advice was to pull the CCU and to inspect the connections for corrosion due to condensation from the center vent. I pulled and checked out the connectors and all look fresh and clean. My only other thought to that article was that maybe the condensation made its way inside the CCU via the vent louvers close to the screen. Very plausible.
I am now on the hunt for a CCU unit that won't cost me $1000.oo. I was looking on eBay but am skeptical of the condition based on their prices starting around $140.oo.
Any thoughts of what else I may be overlooking? I think I've covered the whole system up to the CCU.
In case any of you are attending the Pittsburgh Vintage Grand Prix this weekend (7/19), I will be in attendance with my 996 (despite this issue) and my father with his 997 turbo. Hope to see you out there.
Regards,
Michael
1999 996 Carrera 4
98,800 miles
Sorry it has taken me a while to get back.
Good news. I did not need to have the car towed to my nearest dealer, Sewickley. I called them and was told that the immobilizer was not the issue of the "no crank" and that the immobilizer will not wipe codes in the car. I described the issue and was told to try and push the ignition switch in another 1/8". Sure enough it worked, it just wasn't engaged enough.
So, back to the issue at hand. It turns out it is not the resistor, check that one off the list. Second attempt. I bought a used blower off a salvaged 2001 Carrera with 21,000 miles on it for $54.00. Just installed it this evening and it runs consistent now, but only on the high speed setting. It physically does not run at full speed. And will stop running at roughly 3/4 on the CCU.
I think i've exhausted my options except for the most expensive and I think it might be the issue.
I ran across an article in Rennlist about a 986 where the same symptoms were happening. The advice was to pull the CCU and to inspect the connections for corrosion due to condensation from the center vent. I pulled and checked out the connectors and all look fresh and clean. My only other thought to that article was that maybe the condensation made its way inside the CCU via the vent louvers close to the screen. Very plausible.
I am now on the hunt for a CCU unit that won't cost me $1000.oo. I was looking on eBay but am skeptical of the condition based on their prices starting around $140.oo.
Any thoughts of what else I may be overlooking? I think I've covered the whole system up to the CCU.
In case any of you are attending the Pittsburgh Vintage Grand Prix this weekend (7/19), I will be in attendance with my 996 (despite this issue) and my father with his 997 turbo. Hope to see you out there.
Regards,
Michael
1999 996 Carrera 4
98,800 miles
07-29-2014, 10:23 PM
#42
Instructor
Thread Starter
Join Date: Jul 2002
Location: Morgantown, WV
Posts: 142
Likes: 0
Received 0 Likes
on
0 Posts
FINAL REPORT:
The problem has been solved and all is functioning as normal. But before I get to the final result I want to thank all that posted to solve this issue and to those who followed along. Although I spent roughly $500.00 it would be much much more if it wasn't for everyones input and part searching.
I started off small and began with the typical and much discussed ignition switch. I purchased from Pelican and after pulling the driver seat to access the switch from under the dash and reinstalling, I found that the car would bot turn over. Disappointed and frustrated that the car would not start and thinking I had set the immobilizer, I almost had it towed 1.5 hours to my nearest dealer. But just before making that decision I called the shop manager and described my symptoms and what I had just done. He suggested I get back under the dash and push that switch in another 1/8 inch or so. BINGO! It worked and the car started. But after a quick outburst of joy the blower motor still did not function as normal.
My next decision was to replace the blower motor resistor. I had this issue with my pickup where the blower would not function and it turned out to be a corroded resistor. So, I checked Pelican and discovered they sold for roughly $250.00! That is where you guys chimed in and found some on eBay for $25.00. So i picked one up for $25.00 and pulled the right side of the dashboard apart to replace that resistor. Again, a failed attempt, and I moved on to the next part that could be the culprit, the blower motor.
Back to Pelican and realizing that the blowers run $280.00. Ouch! So I jumped on eBay again after getting such a great price on the resistor and found a seller on eBay that parts out Porsches who had a blower for $56.00 from a donor 2001 coupe with 21,000 miles. It arrived and I installed with no success again.
At this point I am throwing parts at this issue, but I am being very reasonable and realistic with the prices. And I had that feeling numerous times feeling more frustrated after every attempt. The final part to replace was getting closer and closer to the climate control unit. I knew wasn't going to be easy to get or for that matter at a good price.
So, I priced one on Pelican to get an idea. $1122.00 for a new CCU and I still didn't have a guarantee that it was my root cause. No way was I going to spend that much money on a new unit before confirming it was the problem. So I got back on eBay and found a few that were used but had some cosmetic problems for about $125.00 and I also found some priced up to about $750.00. I settled for one for one out of Phoenix, AZ that was a refurbished unit for $175.00 and has a $25.00 core return. It looked good and was refurbished with a 5 year warranty.
So after all the money, parts and time spent on this I finally received the CCU and installed it in about 15 minutes this evening. Problem solved! The blower motor now functions as normal with all speeds functioning. Additionally all functions of the CCU work as directed. And I now have a garage full of spare parts. Anyone need a blower motor or resistor?
Thanks again all.
The problem has been solved and all is functioning as normal. But before I get to the final result I want to thank all that posted to solve this issue and to those who followed along. Although I spent roughly $500.00 it would be much much more if it wasn't for everyones input and part searching.
I started off small and began with the typical and much discussed ignition switch. I purchased from Pelican and after pulling the driver seat to access the switch from under the dash and reinstalling, I found that the car would bot turn over. Disappointed and frustrated that the car would not start and thinking I had set the immobilizer, I almost had it towed 1.5 hours to my nearest dealer. But just before making that decision I called the shop manager and described my symptoms and what I had just done. He suggested I get back under the dash and push that switch in another 1/8 inch or so. BINGO! It worked and the car started. But after a quick outburst of joy the blower motor still did not function as normal.
My next decision was to replace the blower motor resistor. I had this issue with my pickup where the blower would not function and it turned out to be a corroded resistor. So, I checked Pelican and discovered they sold for roughly $250.00! That is where you guys chimed in and found some on eBay for $25.00. So i picked one up for $25.00 and pulled the right side of the dashboard apart to replace that resistor. Again, a failed attempt, and I moved on to the next part that could be the culprit, the blower motor.
Back to Pelican and realizing that the blowers run $280.00. Ouch! So I jumped on eBay again after getting such a great price on the resistor and found a seller on eBay that parts out Porsches who had a blower for $56.00 from a donor 2001 coupe with 21,000 miles. It arrived and I installed with no success again.
At this point I am throwing parts at this issue, but I am being very reasonable and realistic with the prices. And I had that feeling numerous times feeling more frustrated after every attempt. The final part to replace was getting closer and closer to the climate control unit. I knew wasn't going to be easy to get or for that matter at a good price.
So, I priced one on Pelican to get an idea. $1122.00 for a new CCU and I still didn't have a guarantee that it was my root cause. No way was I going to spend that much money on a new unit before confirming it was the problem. So I got back on eBay and found a few that were used but had some cosmetic problems for about $125.00 and I also found some priced up to about $750.00. I settled for one for one out of Phoenix, AZ that was a refurbished unit for $175.00 and has a $25.00 core return. It looked good and was refurbished with a 5 year warranty.
So after all the money, parts and time spent on this I finally received the CCU and installed it in about 15 minutes this evening. Problem solved! The blower motor now functions as normal with all speeds functioning. Additionally all functions of the CCU work as directed. And I now have a garage full of spare parts. Anyone need a blower motor or resistor?
Thanks again all.
07-17-2019, 04:58 AM
#44
Lifting this old thread as I have more or less the same issue as mentioned here, the fan died suddenly a few days ago. The fan doesn't react on the fan speed at all from the CCU and sometimes the fan speed just goes up and down on the CCU.
I have changed/checked the following things.
- Replaced ignition switch
- Removed the fan, it actually works with a 1.5V battery and also with 12V.
- Compared the fan voltage from CCU channel 11 with another 996 and it shows the same value or slightly less.
- All fuses are ok.
- Changed places with relays and they are all ok.
The strange thing here is that when measured the voltage from the fan connector it shows 14V when the engine is running and full fan speed from CCU. If the fan is turned off from the CCU it shows 10V and when car is turned off it shows 0V. Any ideas?
Will try a different CCU when I get hold of one but it still sounds strange that there is voltage to the fan but it doesn't rotate.
I have changed/checked the following things.
- Replaced ignition switch
- Removed the fan, it actually works with a 1.5V battery and also with 12V.
- Compared the fan voltage from CCU channel 11 with another 996 and it shows the same value or slightly less.
- All fuses are ok.
- Changed places with relays and they are all ok.
The strange thing here is that when measured the voltage from the fan connector it shows 14V when the engine is running and full fan speed from CCU. If the fan is turned off from the CCU it shows 10V and when car is turned off it shows 0V. Any ideas?
Will try a different CCU when I get hold of one but it still sounds strange that there is voltage to the fan but it doesn't rotate.
07-24-2019, 03:47 AM
#45
Found a used CCU and now the HVAC fan is working properly.
Strange thing is that now the radiator fans are also working when the snow flake is on. With the bad CCU the radiator fans didn't work even if the snow flake was on, compressor was running and AC pipes were ice cold.
Strange thing is that now the radiator fans are also working when the snow flake is on. With the bad CCU the radiator fans didn't work even if the snow flake was on, compressor was running and AC pipes were ice cold.
