Need Help With A/C pressure sensor
#11
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You would do a visual check of the connector and wiring as far back as possible. Then you would put a voltage meter on it to see if you're get power when a/c is on.
Is there any other codes that your car has? Many things can shut down the system and I want to get the whole picture.
If you are able to engage the compressor via relay then it's something between the relay and compressor.
You are .11kg off on your fill. Add the missing Freon before any more troubleshooting to see if it makes a difference. I'm thinking it will get you back going unless your sensor is still the issue
Is there any other codes that your car has? Many things can shut down the system and I want to get the whole picture.
If you are able to engage the compressor via relay then it's something between the relay and compressor.
You are .11kg off on your fill. Add the missing Freon before any more troubleshooting to see if it makes a difference. I'm thinking it will get you back going unless your sensor is still the issue
To check wires of sensor could I use voltmeter with engine on and clima on? Which value I could read?
About me, problem was compressor but with INPA I can activate air conditioning and air is cold (work well) but fan is always on!
This trouble make me crazy!
#12
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You have a 04 your amount requires 810kg. But I'm not there so I can't make that call.
You test the wire with a voltmeter. back probe the connector with it plugged in and turn on the car and a/c. You should get 12v. If you are getting 12v then test your sensor with an ohm meter. Ensure it is good. If it's good then your issue is with the compressor or pressure. If you are not getting 12v to then test the relay.
You test the wire with a voltmeter. back probe the connector with it plugged in and turn on the car and a/c. You should get 12v. If you are getting 12v then test your sensor with an ohm meter. Ensure it is good. If it's good then your issue is with the compressor or pressure. If you are not getting 12v to then test the relay.
#13
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You have a 04 your amount requires 810kg. But I'm not there so I can't make that call.
You test the wire with a voltmeter. back probe the connector with it plugged in and turn on the car and a/c. You should get 12v. If you are getting 12v then test your sensor with an ohm meter. Ensure it is good. If it's good then your issue is with the compressor or pressure. If you are not getting 12v to then test the relay.
You test the wire with a voltmeter. back probe the connector with it plugged in and turn on the car and a/c. You should get 12v. If you are getting 12v then test your sensor with an ohm meter. Ensure it is good. If it's good then your issue is with the compressor or pressure. If you are not getting 12v to then test the relay.
First of all I'll check quantity (0,810 kg).
after that, with connector plugged and a/c and engine on, I'll check voltage...if I had 12v my problem could be relay. But we're is the relay of iHKA? Have you idea?...
thanks a lot
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Originally Posted by Misterpeppe
Ok Seanjordan...
First of all I'll check quantity (0,810 kg).
after that, with connector plugged and a/c and engine on, I'll check voltage...if I had 12v my problem could be relay. But we're is the relay of iHKA? Have you idea?...
thanks a lot
First of all I'll check quantity (0,810 kg).
after that, with connector plugged and a/c and engine on, I'll check voltage...if I had 12v my problem could be relay. But we're is the relay of iHKA? Have you idea?...
thanks a lot
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Relay: of compressor?...I think it works because with INPA I can activate a/c and air is cold like BMW want!
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The relay should be working I was just letting you know how I would test it.
Everything is pointing a bad pressure sensor. The crazy thing is I've only known the fan to run high when it's over charged but you're saying only 700kg was added to the compressor which is 110kg short of what is recommended. If you can trigger the compressor on through INPA the only thing bypassed is the sensor and IHKA. You are getting voltage when the IHKA is on so it's good. You pressure wire would be the only thing in question other than the sensor itself. If the clutch engaged during freon fill up and pressures are still the same focus on the sensor and connector wires. I would still like to know what your low and high side pressures are to ensure they are correct.
Everything is pointing a bad pressure sensor. The crazy thing is I've only known the fan to run high when it's over charged but you're saying only 700kg was added to the compressor which is 110kg short of what is recommended. If you can trigger the compressor on through INPA the only thing bypassed is the sensor and IHKA. You are getting voltage when the IHKA is on so it's good. You pressure wire would be the only thing in question other than the sensor itself. If the clutch engaged during freon fill up and pressures are still the same focus on the sensor and connector wires. I would still like to know what your low and high side pressures are to ensure they are correct.
#17
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The relay should be working I was just letting you know how I would test it.
Everything is pointing a bad pressure sensor. The crazy thing is I've only known the fan to run high when it's over charged but you're saying only 700kg was added to the compressor which is 110kg short of what is recommended. If you can trigger the compressor on through INPA the only thing bypassed is the sensor and IHKA. You are getting voltage when the IHKA is on so it's good. You pressure wire would be the only thing in question other than the sensor itself. If the clutch engaged during freon fill up and pressures are still the same focus on the sensor and connector wires. I would still like to know what your low and high side pressures are to ensure they are correct.
Everything is pointing a bad pressure sensor. The crazy thing is I've only known the fan to run high when it's over charged but you're saying only 700kg was added to the compressor which is 110kg short of what is recommended. If you can trigger the compressor on through INPA the only thing bypassed is the sensor and IHKA. You are getting voltage when the IHKA is on so it's good. You pressure wire would be the only thing in question other than the sensor itself. If the clutch engaged during freon fill up and pressures are still the same focus on the sensor and connector wires. I would still like to know what your low and high side pressures are to ensure they are correct.
In any case: sensor is new...5 days ago I replaced it and recharged refrigerant but problem not solved.
After charging, with the recharge tool and pipes apply, I started the engine and after 10 seconds fan is started at the maximum speed...tried to activate IHKA and technician told me that was a "puff" like a/c was over charged but only 0,700kg filled.
Could be that the ECU of IHKA are "fused"? (I don't know if there is a ECU)
Could be that problem is a vent motor flap or something like this?..
how to check low and high side pressure?
Sorry for my bad English but it's not easy explain trouble.
The user aadrian (that made post)? He had the same problem and if has solved his "story" could help me!
Last edited by Misterpeppe; 03-16-2021 at 06:28 AM.
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Do you have any other error codes, if so what are they?
The IHKA is its own module. If you turn it on and are getting voltage then it's good.
I understand you just put a new sensor in but I don't ever count that out. I've purchased new parts that were bad. Was the fan running fast when the old one was in?
What program are you using to get your codes? How did you fill your compressor up with freon? To check your system high and low side pressures you need a
. You should of used them when filling your compressor with freon.
Other things can make your fan run fast (thermo, aux pump, etc). If you can send me all the error codes your car has so I can review it. The a/c system is complex but an easy system to diagnose.
The IHKA is its own module. If you turn it on and are getting voltage then it's good.
I understand you just put a new sensor in but I don't ever count that out. I've purchased new parts that were bad. Was the fan running fast when the old one was in?
What program are you using to get your codes? How did you fill your compressor up with freon? To check your system high and low side pressures you need a
Other things can make your fan run fast (thermo, aux pump, etc). If you can send me all the error codes your car has so I can review it. The a/c system is complex but an easy system to diagnose.
#19
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Do you have any other error codes, if so what are they?
The IHKA is its own module. If you turn it on and are getting voltage then it's good.
I understand you just put a new sensor in but I don't ever count that out. I've purchased new parts that were bad. Was the fan running fast when the old one was in?
What program are you using to get your codes? How did you fill your compressor up with freon? To check your system high and low side pressures you need a manifold guage set. You should of used them when filling your compressor with freon.
Other things can make your fan run fast (thermo, aux pump, etc). If you can send me all the error codes your car has so I can review it. The a/c system is complex but an easy system to diagnose.
The IHKA is its own module. If you turn it on and are getting voltage then it's good.
I understand you just put a new sensor in but I don't ever count that out. I've purchased new parts that were bad. Was the fan running fast when the old one was in?
What program are you using to get your codes? How did you fill your compressor up with freon? To check your system high and low side pressures you need a manifold guage set. You should of used them when filling your compressor with freon.
Other things can make your fan run fast (thermo, aux pump, etc). If you can send me all the error codes your car has so I can review it. The a/c system is complex but an easy system to diagnose.
Technician has charged Freon with a manifold station and nothing to tell...all value are good.
Next time I send you all error codes by INPA and iCarly (same code errors). I had 6 glow plug not working, 2 errors in most gw (mulf unplugged) and 1 error fogging sensor...fan not run and all work.
Now I have same error + 9c5e code...and fan run at max speed!
#20
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I can't give you any other advice. The remaining codes do not point to an issue with the cooling system. If your fan was running fast before and after the change and you still have a sensor error it only makes since that the new sensor is bad. I can't give you a definitive answer because of the unknown to me: Knowing the actual pressures of the high and low side. I don't doubt your mechanic but I can't say it is indeed a bad sensor unless the know pressure values. The fan runs fast due to too many things and the only error you have that will make it run fast is the sensor error.