Another AC problem thread
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Another AC problem thread
Tried the reset procedure and pressed front defogger and Recirculate button and it flashes back and forth but doesn't stop at all lol supposed to after 20-30 seconds. Just double checking but to have it cold the temp should be set to "LO" on both sides and that "AC OFF" shouldn't be illuminated right?
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Correct - "AC OFF" should not be on, therefor its indicator light should be extinguished when the compressor is running. It sounds like you have either a damper or ACC module problem. Scanning with SDS can give you exact codes and that will tell us what is wrong.
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Strange how when the "AC off" light is on is more cold then it off . When I press the front defogger it seems to work. Curious how cold does it get? I refilled last year and wasn't cold enough. Last time I got my codes checked from an MB Indy nothing came up (when tranny blew).
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Unless the indy has SDS or a very high end aftermarket scanner specific to MBZ systems, they won't be able to scan codes from the ACC.
Given that your control button is acting strangely, it may be a bad panel instead of a bad damper.
Given that your control button is acting strangely, it may be a bad panel instead of a bad damper.
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Maybe it's a fuse? Not sure where to begin. Should I just try refilling it?
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If you have gauges and can check pressures, you can add refrigerant, but if the "Self test" has failed, then there is an error code stored in the ACC and that will be the key to telling us what is wrong and how to correct it.
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I recharged it last year without the oil, guess I should start using the oil but no clue where to or how to add oil to it
Ps couldn't find a leak, should I try that sealant thing?
Ps couldn't find a leak, should I try that sealant thing?
Last edited by Rogue-CLK; Jun 3, 2014 at 10:56 PM. Reason: More info
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If you just "topped off" the refrigerant with one of those recharge kits, then don't worry about the oil. You really onyl need to add oil if you lose all the refrigerant or are replacing parts (in which case you have discharged an evacuated the system, thus starting from empty).
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Then yes I've only "topped up" is that ok though? Like keep topping it off without ever evacuating the system. I check my pressure and it's at 10 so well below what it should b at which is... 45-50?
Last edited by Rogue-CLK; Jun 3, 2014 at 11:09 PM. Reason: Spelling error
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I'm a bit lost, first there's R12 "bad" that got replaced by R134a "good" but now I see this 12a that replaces the "old R134a" I should just stick with R134a right? They say 12a is "colder" and uses 1/3 of its counterpart true?
Last edited by Rogue-CLK; Jun 4, 2014 at 05:45 PM.
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Well I bit the bullet and hope I don't get shot lol used (1) 6oz can of 12a equivalent to 16oz of R134a. Pressure after 1 can was 35 psi while car was on and AC running. While car was off it was at 60 psi. High side didn't bother. Since I achieved 35 psi I assume it's full?
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Do you have gauges or were you using the recharge kit's gauge? If you aren't using professional gauges, don't even think about trying to check the high side. I think anything below 35psi on the low side (while running) is good. Recharging like this works best on a very hot day - run the AC on max. On cooler days, place the can in warm water to help it vaporize.
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I actually have both but used the recharge kit(just low side gauge) couldn't find exactly where the high side was, googled and only saw low side :/. Assuming I add more, the psi reading will go higher right?
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Here's a good chart to use:
http://acprocold.com/faq/r-134a-system-pressure-chart/
Note that being low on refrigerant will generally cause the low side to read higher, now lower.
http://acprocold.com/faq/r-134a-system-pressure-chart/
Note that being low on refrigerant will generally cause the low side to read higher, now lower.
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Based on the chart, without knowing what the high side psi is, it's working properly it's blowing colder air than R134a. Oh and the 12a has a dye in it and haven't physically seen any green leaks... Unless I need some other glasses or uv light something LOL
