Camnefdt
Member
Here's my adventures of the past week, with the hope that it would help one of you guys in the future.
I bought my 2011 e90 320D last Saturday with the knowledge of the AC not working. According to seller, "It suddenly stopped working 2 months ago, tried to re-gas it but didn't fix it."
The assumption at this point based on information provided was most likely either AC compressor or AC clutch. When I had a look at the vehicle, tried it out and clutch was not kicking in which then would point at electrical issue or AC clutch itself.
I live in Durban, there's no chance I'm driving around without a functioning AC, so first thing Sunday morning I had my head in the passenger foot well looking at fuses and checking they were all good. First indicator of a bit more to the story was finding the mounts for the pivot on the glove box were broken off, and the junction box module looked to have been messed with. Ignored this for now because "AC was working up until 2 months ago".
Fuses all checked out good, and just as a ease the mind test, I decided to give the AC clutch direct 12V and see if it will activate. As soon as power is given, clutch engaged which eliminated the clutch as the issue. At this point, there wasn't much I could do without some kind of diagnostics cable, so made an order for an OBDII cable and had to wait.
Cable arrived on Wednesday and I immediately got started with loading BMW tools on my laptop to start diagnosing and reading faults. Launch INPA, do full read and load fault list and right at the top, the very first error in big red- "C91D! Message (compressor clutch, 0x246) error, receiver JBE, transmitter IHKA" - Ok that doesnt sound good, but I have only basic knowledge, it doesn't really mean all too much to me haha.
So I started checking sensors, checking functions and everything was looking good. I could activate the AC clutch from INPA and it would engage, then I started thinking about the Junction box module having looked messed with. After a quick discussion with the previous owner, he admitted to having the junction box module repaired and refitted in December, but the AC only stopped working in Feb. So now with having the error at the JBE and the previous owner having admitted to repairs being done to the JBE, that's where I started thinking towards. The only thing that didn't make sense to me was that I could still activate the AC clutch through INPA, which the signal comes from the JBE module.
It was too late at this point to continue on Wednesday so decided to leave it and start doing some research. I am very fortunate that I happen to have some really awesome people around me with very high level of skills and one individual in particular who stays in JHB happens to specialize in BMW ECU repairs and has an excellent knowledge on the BMW electrical systems. I spoke to him about the issue and he had a few ideas of what it could be, he looked at the error code and immediately saw what I missed. The error code is because of a communication error from the climate control unit to the junction box module. So Thursday morning, he remoted into my laptop while I was connected up and did his thing.
First thing to check- Do we have access to the climate control module- Yes we did, awesome, that's good news, its not completely poked. Next check- Is the software on the climate control correct- and there it was, an incorrect VIN programmed on the AC climate control unit. So at some point the climate control unit was swapped out with a different one, and the system was never programmed or it was incorrectly programmed. We reprogrammed the IHKA and tested. Finally the clutch was kicking in like it was supposed to, not yet getting cold but at least functioning.
Yesterday I took it in and got the AC fully serviced and re-gassed and shes cold as ice!!
Moral of the story- Never trust the word of the person you buying the car from, never take their word for something having being checked and do your own checks from the beginning. Instead of having to replace the AC compressor or AC clutch, it cost me 1X diagnostics cable R399 which I now have for anything I need to do, and 1X AC service and fill-up.
I bought my 2011 e90 320D last Saturday with the knowledge of the AC not working. According to seller, "It suddenly stopped working 2 months ago, tried to re-gas it but didn't fix it."
The assumption at this point based on information provided was most likely either AC compressor or AC clutch. When I had a look at the vehicle, tried it out and clutch was not kicking in which then would point at electrical issue or AC clutch itself.
I live in Durban, there's no chance I'm driving around without a functioning AC, so first thing Sunday morning I had my head in the passenger foot well looking at fuses and checking they were all good. First indicator of a bit more to the story was finding the mounts for the pivot on the glove box were broken off, and the junction box module looked to have been messed with. Ignored this for now because "AC was working up until 2 months ago".
Fuses all checked out good, and just as a ease the mind test, I decided to give the AC clutch direct 12V and see if it will activate. As soon as power is given, clutch engaged which eliminated the clutch as the issue. At this point, there wasn't much I could do without some kind of diagnostics cable, so made an order for an OBDII cable and had to wait.
Cable arrived on Wednesday and I immediately got started with loading BMW tools on my laptop to start diagnosing and reading faults. Launch INPA, do full read and load fault list and right at the top, the very first error in big red- "C91D! Message (compressor clutch, 0x246) error, receiver JBE, transmitter IHKA" - Ok that doesnt sound good, but I have only basic knowledge, it doesn't really mean all too much to me haha.
So I started checking sensors, checking functions and everything was looking good. I could activate the AC clutch from INPA and it would engage, then I started thinking about the Junction box module having looked messed with. After a quick discussion with the previous owner, he admitted to having the junction box module repaired and refitted in December, but the AC only stopped working in Feb. So now with having the error at the JBE and the previous owner having admitted to repairs being done to the JBE, that's where I started thinking towards. The only thing that didn't make sense to me was that I could still activate the AC clutch through INPA, which the signal comes from the JBE module.
It was too late at this point to continue on Wednesday so decided to leave it and start doing some research. I am very fortunate that I happen to have some really awesome people around me with very high level of skills and one individual in particular who stays in JHB happens to specialize in BMW ECU repairs and has an excellent knowledge on the BMW electrical systems. I spoke to him about the issue and he had a few ideas of what it could be, he looked at the error code and immediately saw what I missed. The error code is because of a communication error from the climate control unit to the junction box module. So Thursday morning, he remoted into my laptop while I was connected up and did his thing.
First thing to check- Do we have access to the climate control module- Yes we did, awesome, that's good news, its not completely poked. Next check- Is the software on the climate control correct- and there it was, an incorrect VIN programmed on the AC climate control unit. So at some point the climate control unit was swapped out with a different one, and the system was never programmed or it was incorrectly programmed. We reprogrammed the IHKA and tested. Finally the clutch was kicking in like it was supposed to, not yet getting cold but at least functioning.
Yesterday I took it in and got the AC fully serviced and re-gassed and shes cold as ice!!
Moral of the story- Never trust the word of the person you buying the car from, never take their word for something having being checked and do your own checks from the beginning. Instead of having to replace the AC compressor or AC clutch, it cost me 1X diagnostics cable R399 which I now have for anything I need to do, and 1X AC service and fill-up.
