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Troubleshooting No Heat

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11 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

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YOUR RESEARCHTroubleshooting No Heat

Leading reported evidence

Use temperature control button even if the engine is cold

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
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Unsuccessful attempts
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0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

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Suggestion

The air speed/flow (something) changes perceptibly (I can hear it and feel it) as I cycle the heater temperature control from low to high using the temperature control button even if the engine is cold.

Troubleshooting No Heat
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Leading evidence: 'Use temperature control button even if the engine is cold' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Use temperature control button even if the engine is cold' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

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1 matching discussions · 11 captured posts examined · 0 partial discussions

Frequently discussed actions (1)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Use temperature control button even if the engine is cold

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

The air speed/flow (something) changes perceptibly (I can hear it and feel it) as I cycle the heater temperature control from low to high using the temperature control button even if the engine is cold.

Troubleshooting No Heat
Coverage and how to read this overview

Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.

11 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

  • Rennlist: 1 discussions

0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.

0 acknowledgements have no verified action link; they do not establish a repair result.

Generation: 20261027T154520Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

I am wondering where to start troubleshooting my no heat problem- by no heat I mean even when set to hi, the air blowing out is ambient. The hoses going to the heater core are both hot to the touch when the engine is warm so I don't believe its a trapped air thing... Where do I begin with verifying the operation of the various flaps?

POST 2Original post

Quotes source post: 10675439

If the hoses to/from the heater core are hot then I think you have narrowed the problem down to a heater flap issue. The flap has failed and dropped down -- or stuck in an fully up position -- so no air is routed through the heater core. With the auto climate I believe the Porsche diagnostics computer can "talk" to the controller and command certain operations and and allow the tech to trouble shoot the system With the manual system I'm less sure the diagnostics computer can do much with it. What can you do? Well, if you operate the heater temperature control does the air speed or flow change? The air speed/flow (something) changes perceptibly (I can hear it and feel it) as I cycle the heater temperature control from low to high using the temperature control button even if the engine is cold. I take this as a sign the air flap is moving and routing air around/past the the heater core then through it as the temperature control setting is increased.

POST 4 / ORIGINAL POSTEROriginal post

I am located in Lancaster CA So when I have the vents configured as in the first picture, as I go from cold to hot, the air output transitions from the center vent only at max cold to the footwell and windshield at max hot. When configured as pictured here, or any combination of windshield, center, or footwell only the air output does not vary as the temp control is changed.

POST 5Original post

Quotes source post: 10676413

I've been through Lancaster. Drove over from 395 then took 14 up to Mojave and then 58 over to Tehachapi and on into Bakersfield. Unfortunately I do not recall anything of note. I just passed through in a hurry to get someplace else.

POST 6 / ORIGINAL POSTEROriginal post

Nothing of note- hah that's pretty much true but its because all the cool stuff is hidden away from public view! There are some really cutting edge vehicles being developed just a stone's throw from the 14, you can probably actually see the buildings. Aerospace is the main reason the Palmdale/Lancaster area is as big as they are, I actually work in Mojave, but could not bear to live there. Plus, the 996 would look incredibly out of place in that area I would probably get shot at haha

POST 7 / ORIGINAL POSTEROriginal post

Well, good news is my heater core is in great shape, as well as the foam on my flap... bad news is the flap doesn't move at all. Servo arm here I come!

POST 8Original post

I knew there was a lot of hispanics in Socal (lived there for a while)Now my old gardener , Manuel, is your HVAC mechanic!!!

POST 9 / ORIGINAL POSTEROriginal post

Ay Caramba! Too bad I took French maybe I could communicate with it better haha Well, the servo checks out, I put 12v to the motor manually and it moves just fine, both directions. Also confirmed no voltage from the harness side when cycling temp controls. Bad climate control unit is the answer I fear. Also from https://rennlist.com/forums/996-foru...e-control.html my 12c command value varies properly, and as I manually turn the motor and move the servo arm, the 13c position value varies correctly. I hooked a multimeter up to the motor and there is nothing...must be internal to the climate control unit

POST 10 / ORIGINAL POSTEROriginal post

Alright well a little logic and a multimeter can go a long way! I opened up the climate control unit hoping to find a cold solder joint or a toasted transistor, but on a whim I also wiped down all the contacts in the back and what do you know the servo came back to life! Definitely will reassemble with dielectric grease...

POST 11Original post

Quotes source post: 10680356

I know this is old but thus killed me 😂😂😂

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