mamabear Posted February 16, 2011 Share Posted February 16, 2011 Ok guys, I have joined this forum to see if y'all might be able to help me help my man!He is in a 2010 Mack and having a/c issues. It blows nothing but hot air. He has had it in the shop dozens of times for the same issue, but it still isn't being fixed. He can get down the road a few hundred miles and it does it again.I am gonna be honest and tell you that I have no idea about vehicles, much less Macks - but I need to know if there is somewhere I can help him troubleshoot this issue.Thanks!D Quote Link to comment Share on other sites More sharing options...
Rob Posted February 16, 2011 Share Posted February 16, 2011 Ok guys, I have joined this forum to see if y'all might be able to help me help my man!He is in a 2010 Mack and having a/c issues. It blows nothing but hot air. He has had it in the shop dozens of times for the same issue, but it still isn't being fixed. He can get down the road a few hundred miles and it does it again.I am gonna be honest and tell you that I have no idea about vehicles, much less Macks - but I need to know if there is somewhere I can help him troubleshoot this issue.Thanks!DBe glad to help you but need more information for diagnosis. Does the unit blow cold air just after being serviced? Does the system lose it's refrigerant charge? Does the binary, or trinary switch actuate shutting the system down. Does the compressor run for a short while then cease?There are many indicators available to drill down to the affected parts or symptom and warm air when should be cold, is to vague.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment Share on other sites More sharing options...
hatcity Posted February 16, 2011 Share Posted February 16, 2011 A/C filter replaced recently? Quote Success is only a stones throw away.................................................................for a Palestinian Link to comment Share on other sites More sharing options...
mamabear Posted February 16, 2011 Author Share Posted February 16, 2011 Be glad to help you but need more information for diagnosis. Does the unit blow cold air just after being serviced? Does the system lose it's refrigerant charge? Does the binary, or trinary switch actuate shutting the system down. Does the compressor run for a short while then cease?There are many indicators available to drill down to the affected parts or symptom and warm air when should be cold, is to vague.RobOk Rob - to get started, yes, it does blow cold air after being serviced. He said the system isn't showing that the refrigerant is being lost. He said he doesn't know on the switch question and as far as the compressor, he said it keeps blowing.Hatcity - the filter was replaced within the last month. He has checked both to be safe on that as well.Thanks for the help guys - he is in FL right now and not happy because he has no a/c and its in the 70s! Quote Link to comment Share on other sites More sharing options...
Rob Posted February 17, 2011 Share Posted February 17, 2011 Ok Rob - to get started, yes, it does blow cold air after being serviced. He said the system isn't showing that the refrigerant is being lost. He said he doesn't know on the switch question and as far as the compressor, he said it keeps blowing.Hatcity - the filter was replaced within the last month. He has checked both to be safe on that as well.Thanks for the help guys - he is in FL right now and not happy because he has no a/c and its in the 70s!I realize it is difficult to be third party and relay accurate information but more information as to how the cooling "falls off" is needed. You've indicated the system does not show the refrigerant being lost? I'm interested in how this is evaluated. An automotive air conditioning system is fully closed and not open to atmosphere so in theory should never be low of charge. This is not so true in practice. However from the description given after service the unit does work, (temporarily) and then the discharge air warms, with no loss of refrigerant, is an indication of either a restriction in the system, or defective parts someplace. Air conditioning systems are protected from both over, and under pressure. It takes refrigerant to circulate the oil in the system to lubricate mechanical parts. A loss of refrigerant will open a switch disallowing the compressor to function for protection. Also a/c systems make quite high pressure on the discharge side of the compressor. This is limited as a safety precaution also. Overpressure will also disable compressor operation. Either an undercharge, overcharge, or restriction in the dryer/accumulator, collapsed tube in the condensor, faulty thermostatic expansion valve or fixed orifice tube can give the symptoms described. In most never vehicles, if a fault is sensed in the system, the ECU will shut down and lock the system out preventing further operation till the fault is cleared from memory. I don't know if Mack does this or not.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment Share on other sites More sharing options...
rhasler Posted February 17, 2011 Share Posted February 17, 2011 I realize it is difficult to be third party and relay accurate information but more information as to how the cooling "falls off" is needed. You've indicated the system does not show the refrigerant being lost? I'm interested in how this is evaluated. An automotive air conditioning system is fully closed and not open to atmosphere so in theory should never be low of charge. This is not so true in practice. However from the description given after service the unit does work, (temporarily) and then the discharge air warms, with no loss of refrigerant, is an indication of either a restriction in the system, or defective parts someplace. Air conditioning systems are protected from both over, and under pressure. It takes refrigerant to circulate the oil in the system to lubricate mechanical parts. A loss of refrigerant will open a switch disallowing the compressor to function for protection. Also a/c systems make quite high pressure on the discharge side of the compressor. This is limited as a safety precaution also. Overpressure will also disable compressor operation. Either an undercharge, overcharge, or restriction in the dryer/accumulator, collapsed tube in the condensor, faulty thermostatic expansion valve or fixed orifice tube can give the symptoms described. In most never vehicles, if a fault is sensed in the system, the ECU will shut down and lock the system out preventing further operation till the fault is cleared from memory. I don't know if Mack does this or not.RobRob, this truck probably has an APADS system. Basically an independent controller for the A/C system that communicates various system conditions through a series of flashing lights. Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment Share on other sites More sharing options...
Rob Posted February 17, 2011 Share Posted February 17, 2011 Rob, this truck probably has an APADS system. Basically an independent controller for the A/C system that communicates various system conditions through a series of flashing lights.I certainly wouldn't have any knowlege of anything like that. What is APADS an acronym for?Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment Share on other sites More sharing options...
rhasler Posted February 17, 2011 Share Posted February 17, 2011 I certainly wouldn't have any knowlege of anything like that. What is APADS an acronym for?RobIt stands for air-conditioning protection and diagnostics system (had to look it up myself). The system works more or less the same as traditional systems, it just has a controller wired inline to all of the inputs from the various sensors and switches that controls output to the compressor clutch. Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment Share on other sites More sharing options...
rhasler Posted February 17, 2011 Share Posted February 17, 2011 Here are the blink codes for the APADS controller which are flashed out on the LEDs of the control unit. The 2010 chassis in question should be using the CM813 controller. Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment Share on other sites More sharing options...
mamabear Posted February 17, 2011 Author Share Posted February 17, 2011 Thanks guys. I will get with him this morning and review all this info and let you know what we find next.I do appreciate the help - he isn't havin too much fun with the temperatures in FL right now. Quote Link to comment Share on other sites More sharing options...
Gambi80 Posted February 17, 2011 Share Posted February 17, 2011 Thanks guys. I will get with him this morning and review all this info and let you know what we find next.I do appreciate the help - he isn't havin too much fun with the temperatures in FL right now.I would be though... Quote Ever wonder how a blind person knows when to stop wiping? Link to comment Share on other sites More sharing options...
mamabear Posted February 17, 2011 Author Share Posted February 17, 2011 Ok guys - he got to the shop today and they changed out the sensor. It worked, for about 10 minutes and now it isn't working anymore.He has played with some of the wiring on it as well, and it started workin again for another 5 minutes and it is now not working again... I gave him the list of the codes you posted, he is going to see what he can figure out there, but if you have any other suggestions - please let me know.Thanks again! Quote Link to comment Share on other sites More sharing options...
Mackpro Posted February 18, 2011 Share Posted February 18, 2011 Whats the last 6 of the VIN and model number (GU713- CXU613...ect) I can pull it up and see what AC set-up you got. Quote Link to comment Share on other sites More sharing options...
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