A/C fluctuates - works, but goes High and Low

Andy Rubalcaba · Apr 17, 2021

Air Conditioner is fluctuating between High and Low, I keep it on low but it keeps going up and down and won't stay stable. anyone deal with this before?

i'm thinking bad battery because my side mirrors also stopped working and my seat won't adjust anymore. I haven't tested it yet cause i've been busy, I imagine it's in the realm of possibility to be due to the battery ( I have no history on the battery but previous owner thought it was a good idea to get a cheap walmart battery so I want to replace this anyways ).

99WhiteC5Coupe · Apr 17, 2021

Andy Rubalcaba said:
Air Conditioner is fluctuating between High and Low, I keep it on low but it keeps going up and down and won't stay stable. anyone deal with this before?

i'm thinking bad battery because my side mirrors also stopped working and my seat won't adjust anymore. I haven't tested it yet cause i've been busy, I imagine it's in the realm of possibility to be due to the battery ( I have no history on the battery but previous owner thought it was a good idea to get a cheap walmart battery so I want to replace this anyways ).

Year, make and model?

Do you mean the airflow with the a/c is fluctuating - or the cooling?

I would bet the battery and/or dirty, corroded or loose battery terminal connectors.

Andy Rubalcaba · Apr 17, 2021

99WhiteC5Coupe said:
Year, make and model?

Do you mean the airflow with the a/c is fluctuating - or the cooling?

I would bet the battery and/or dirty, corroded or loose battery terminal connectors.

well, it's of course a 3rd gen expedition lol. it's an 08 EL Limited, as far as the trim.

it's just the fan speed that fluctuates, and one day it didn't work at all until later again that night.

Hamfisted · Apr 17, 2021

Don't be surprised if your blower control module is failing.

https://www.rockauto.com/en/catalog...g,blower+motor+control+module+/+resistor,6557

Yupster Dog · Apr 17, 2021

Andy Rubalcaba said:
cheap walmart battery so I want to replace this anyways

Your on the right track, get the steady reliable power then start your diagnosis.

I also recommend doing a Voltage Drop Test to make sure the power is getting to where it is suppose to
If it keeps on being a few electrical problems but they don't seem related, It could be a lifted ground somewhere.

07navi · Apr 17, 2021

Change that battery and then get back to us.

Andy Rubalcaba · Apr 18, 2021

thanks guys i'll be getting a new battery tomorrow or the next day, as I end my work week.

and thanks for the part link and voltage video, good stuff!

rsupak · Jun 21, 2024

Did you ever get this fixed...I just noticed mine started doing this?

mgp1231 · Jun 21, 2024

I also have a 2008 EL but mine is the Eddie Bauer edition. I had similar AC symptoms but also had temperature changes. Battery replacement cured my AC issues.

A/C fluctuates - works, but goes High and Low

Andy Rubalcaba

Full Access Members

99WhiteC5Coupe

Full Access Members

Andy Rubalcaba

Full Access Members

Hamfisted

Full Access Members

Yupster Dog

Super Moderator

07navi

Full Access Members

Andy Rubalcaba

Full Access Members

rsupak

New Member

mgp1231

New Member

Similar threads

Latest posts

Members online

Forum statistics

Share this page