Jump to content

The RennTech.org community is Member supported!  Please consider an ANNUAL donation to help keep this site operating.
Click here to Donate

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)
Sign in to follow this  
enoteche

HVAC System Delay on Start

Recommended Posts

Hello,

 

I have recently purchased a 2004 CTT, I haven't driven it much (travelling for work) but I have an issue when I start it up that happens now and then...

 

The HVAC system will not immediately come on, sometimes it will kick on a minute later, sometimes it will take up to 3 minutes.  Sometimes it sounds like the vents under the dash are opening and closing right after the Cayenne is turned on before air runs thru the ducts.

 

Is there some sort of relay switch going bad, or some sort of setting on the HVAC controls that needs changed?

 

 

Thank you

Share this post


Link to post
Share on other sites
    You can remove these ads by becoming a Contributing Member.

When your battery is low on charge the ancillaries won't come on until it is charged back up to a certain level, which it will do after a minute or two of driving.  Either you've got an excessive draw on your battery when your Cayenne is parked or your battery needs replacing or both. Usually it's just the battery.

Share this post


Link to post
Share on other sites

Yes, this is a *feature* to protect the electronics.  The HVAC blower will draw enough current to dip the car's voltage and possibly create voltage stability issues with the ECU, etc.

 

I'd charge the battery now and place it on a trickle charger while away for extended periods (7 days+).

Share this post


Link to post
Share on other sites

Thank you for the suggestions.

 

I had changed the battery a few days after I made this post and everything seemed fine for the most part.

 

My wife has used this car as a daily driver but she only drives about 4 miles round trip.

 

Occasionally the automatic locks won't work, and the HVAC system is delayed on start up like before.  It isn't happeneing as frequently but it's still happening on days it's ran and turned on and off several times.

 

I am guessing I have an excessive draw somewhere, but any last suggestions before I take it to a mechanic?

 

I still need to purchase a trickle charger, but am I going to need to put in on a trickle everyday?  Seems excessive.

Edited by enoteche

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.