HVAC climate control

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Aug 8, 2023 | 12:36 PM

jess

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HVAC climate control

Hi everyone

The on/off switch on my AC climate control module does not work. I removed it and made the 16 solder joints but it still does not come on. I am getting the small lights that come on. Is there a power relay or a fuse to replace before I locate a new or rebuilt unit.
thanks in advance.

2001 C5
2014 C7
1995 C4
Porsche 911 SC

Aug 8, 2023 | 03:18 PM

yellow2007

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From: Conyers Georgia

Could be as simple as a burnt bulb

Aug 8, 2023 | 03:39 PM

jess

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Would a burned out bulb keep the whole unit from turning on?

Aug 8, 2023 | 04:11 PM

yellow2007

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From: Conyers Georgia

Quote:

Originally Posted by jess

Would a burned out bulb keep the whole unit from turning on?

No but it's an indication of a problem with the controller. There's a service that yu can send the unit to that repairs it and replaces the lights with led's

Aug 8, 2023 | 05:39 PM

jess

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My original question is

Before I spend money to renew, replace my unit, is there a relay, power supply etc. that I should look at first.

Aug 8, 2023 | 06:18 PM

C5 Diag

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From: Cape Coral, Florida

Quote:

Originally Posted by jess

My original question is

Before I spend money to renew, replace my unit, is there a relay, power supply etc. that I should look at first.

I would first check to see if you have any trouble codes stored using either a scan tool or the DIC…you can check HVAC fuse 27 which is battery power to the HVAC module…see if you have any “no comms” stored in the HVAC module…you really need either a factory level or aftermarket bidirectional scan tool to see if the HVAC module is seeing your “input” to the module…basically your finger pushing on the AC button…if the input is good the module will see that input.

Aug 8, 2023 | 06:33 PM

jess

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That’s what I needed, thank you

Aug 9, 2023 | 04:05 PM

redzg

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From: Orlando Florida

There are both off and on buttons on the control. If you have the engine running and press the off button, wait a beat, then press the auto button does nothing happen? No indicator lights for A/C or recirculate vs fresh illuminate, etc? Defroster buttons do not illuminate if pressed?