Porsche CC Repair

Important: Use this guide if you reinstalled your repaired (Porsche Climate Control Module) and the problem is still happening.
Important: Please do not open/disassemble the module.

• Step 1: Confirm the exact symptom
  • No response from buttons/knobs
  • Blower runs full speed all the time
  • No communication / HVAC control module not responding (scan tool if equipped)
  • Intermittent operation (works warm/cold, fails on bumps)
• Step 2: Quick reset (common after reinstall)
  • Key off, remove key, wait 2 minutes
  • Disconnect battery for 5 minutes (if accessible), reconnect
  • Re-test with engine running (low voltage during cranking can cause odd behavior)
• Step 3: Verify connector seating and pin condition
  • Unplug and re-plug all climate control connectors until they fully seat/lock
  • Inspect for bent pins, pushed-out terminals, corrosion/green discoloration, or loose pin fitment
  • Make sure the harness isn’t pulling sideways on the connector after reinstallation
• Step 4: Check HVAC-related fuses and power feeds
  • Check fuses for HVAC/climate control, blower/aux fan, and ignition-switched feed
  • If a fuse is blown, replace once and re-test
  • If it blows again, stop and inspect for a short in vehicle wiring/components
• Step 5: If the blower is stuck on HIGH all the time
  • This is often vehicle-side, not the control head
  • Inspect the blower resistor / final stage unit (blower power stage) depending on model
  • Check for a shorted blower power transistor/module or melted connector at the blower control/resistor
  • Verify the blower motor isn’t drawing excessive current (worn motor can overheat and damage the power stage)
• Step 6: If the control head is unresponsive (buttons/knobs do nothing)
  • Confirm the unit has power and ground at the connector (a bad ground can mimic a failed module)
  • Inspect dash grounds near the center console and any ground straps disturbed during interior work
  • If the issue began after radio/console work, re-check any connectors that were recently unplugged
• Step 7: If “no communication” is reported
  • Verify vehicle power/ground first (module can’t communicate if it’s browning out)
  • Inspect the connector pins for corrosion/loose tension (common on older vehicles)
  • If available, scan for related network/body codes and clear/retest after the symptom returns
• Step 8: Intermittent faults (heat/vibration related)
  • With the unit installed and powered, lightly wiggle the harness near the connector
  • If the symptom changes, suspect loose terminals, partially backed-out pins, or harness strain behind the dash
• Step 9: If symptoms point to air distribution or temperature issues
  • If the display/buttons are working but airflow direction or temperature is wrong, the cause is usually vehicle-side:
    • vacuum supply leak (if vacuum-controlled doors)
    • broken vacuum lines
    • failed blend/mode actuators or linkage
  • These issues won’t be corrected by the control head alone
• Step 10: Still not resolved?
  • If fuses, connectors, and power/ground check out and the problem remains, the most likely causes are blower power stage/resistor, blower motor current draw, vacuum leaks, or actuator/linkage faults. A qualified local shop may be needed for hands-on diagnosis.