Blend door actuator - hot again
Thread Starter
Cruising
Joined: Dec 2023
Posts: 13
Likes: 4
Blend door actuator - hot again
I replaced both blend door actuators left and right two years ago. I bought good recommended parts. That fix provided controllable cool/warm changes to the automatic climate control system left and right temp ***** so it was not full hot all the time. I was getting good results for two years.
Now, the right side is behaving but the left side is back to hot. Not full hot but somewhere in the middle. With key on, Eng off, I can hear the two actuators moving so I don’t believe I lost an arm. I did a good job replacing these I’m certain.
i have no current or historical hvac codes in the DIC.
Is there a means to reset the hvac system?
Could it be my hvac head unit?
Or is the left actuator likely toast and probably its plastic gear ruined like I found in the original two I replaced? Is two years all we can get out of these? I’ve only got 6,000 mi in two years and garaged and not driven hard.
Now, the right side is behaving but the left side is back to hot. Not full hot but somewhere in the middle. With key on, Eng off, I can hear the two actuators moving so I don’t believe I lost an arm. I did a good job replacing these I’m certain.
i have no current or historical hvac codes in the DIC.
Is there a means to reset the hvac system?
Could it be my hvac head unit?
Or is the left actuator likely toast and probably its plastic gear ruined like I found in the original two I replaced? Is two years all we can get out of these? I’ve only got 6,000 mi in two years and garaged and not driven hard.
Thread Starter
Cruising
Joined: Dec 2023
Posts: 13
Likes: 4
In my 1999, passenger floor fuse box, I’ve got fuses 18 and 27 both titled “HVAC Controls”. Do I remove both for one minute? I tried to search a bunch of these exact terms you posted to get more detail. Nothing else in this panel references HVAC.
Thread Starter
Cruising
Joined: Dec 2023
Posts: 13
Likes: 4
Tried the process, but the left side is still hot. Repeated the process a second time with same results. No codes thrown or parked in the DIC. Turning the left or right temp **** up or down yields no change. After I did the process and started the car, I let the hvac settle for three minutes. While it didn’t do anything it was set on auto.
A/C now does not yield cool/cold air. My A/C compressor, water pump, lines, etc are only two yrs old. Had ice cold air before.
I unplugged the battery for two hours and found no improvement anywhere afterwards.
I’ll take it to my local shop to diagnose. I can’t imagine I’d have a Freon leak. I have already done a full inspection under the battery tray. Entire region is in excellent shape and no apparent vacuum leaks. I’d have codes set anyway. This is indeed odd.
Thank you much for the help though. I do appreciate you.
if I had to bet, both of my blend door actuators are probably toast. Again, they have 6,000 mi on them though. Where does one purchase high quality actuators today? Dealer available? I’ll let the shop tell me what they suggest first.
A/C now does not yield cool/cold air. My A/C compressor, water pump, lines, etc are only two yrs old. Had ice cold air before.
I unplugged the battery for two hours and found no improvement anywhere afterwards.
I’ll take it to my local shop to diagnose. I can’t imagine I’d have a Freon leak. I have already done a full inspection under the battery tray. Entire region is in excellent shape and no apparent vacuum leaks. I’d have codes set anyway. This is indeed odd.
Thank you much for the help though. I do appreciate you.
if I had to bet, both of my blend door actuators are probably toast. Again, they have 6,000 mi on them though. Where does one purchase high quality actuators today? Dealer available? I’ll let the shop tell me what they suggest first.
Thread Starter
Cruising
Joined: Dec 2023
Posts: 13
Likes: 4
My shop says the left actuator needs to be replaced or re-indexed. Cool air on right, warm on left. I tried the factory reset fuse 27 procedure multiple times but no luck. The left side never goes cold.
I can hear the left motor moving to both stops to what seems like the same distance as the right motor. It seems to have complete travel with the key on and moving the motors is my point. Maybe the left mechanical door is getting worn out. I’ll see if I can re-index the left motor by turning the teeth further towards cold. I found a post here that says two teeth CCW for the left side after you crack the case open.
I had to crack open the plastic heater box with a saw on my 1999 ford pickup to replace the mechanical heater door that had a cracked post where the blend door actuator attaches. That fixed the temp issue. Does the C5 have a similar plastic door and plastic post? Anyone know? Would be near impossible to replace I bet.
I can hear the left motor moving to both stops to what seems like the same distance as the right motor. It seems to have complete travel with the key on and moving the motors is my point. Maybe the left mechanical door is getting worn out. I’ll see if I can re-index the left motor by turning the teeth further towards cold. I found a post here that says two teeth CCW for the left side after you crack the case open.
I had to crack open the plastic heater box with a saw on my 1999 ford pickup to replace the mechanical heater door that had a cracked post where the blend door actuator attaches. That fixed the temp issue. Does the C5 have a similar plastic door and plastic post? Anyone know? Would be near impossible to replace I bet.
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