My air conditioning unit has ceased functioning. Recently, it occasionally ceased functioning, but now it has completely stopped operating. I suspected it was low on fuel, so I proceeded to recharge it. Nevertheless, it was unfeasible to complete it. It ceased at around 410 grams of gas, despite the successful completion of all prior experiments. I conducted a diagnostic using ISTA, which indicated a fault in the AC module related to the compressor's clutch failing to engage. Attempted to activate it manually without success. I attempted to activate the auxiliary fan via ISTA, but it was unsuccessful as well. There are no faults in the DME for the auxiliary fan. I attempted to scan the vehicle using INPA but was unable to establish a connection.
My inquiry is: do you believe the issue is with the compressor's clutch, the auxiliary fan, or another component?
Thank you in advance
The air conditioning is inoperative, and the auxiliary fan is also nonfunctional. BMW X5 E53 3.0d
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matthewlightburn
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Several years ago, my device ceased functioning due to a malfunctioning fan.
I am uncertain how to do a test, since I lack expertise in electronics; I just acquired a second-hand fan, and it functioned properly once again.
I am uncertain how to do a test, since I lack expertise in electronics; I just acquired a second-hand fan, and it functioned properly once again.
If the clutch fails to engage manually, it is defective. How did you ascertain this? You can assess the resistance of the clutch; if it is very high or open, it is defective. If the fan is defective, a corresponding error code will be generated. If the system was not regassed due to a leak identified during the precharge or pressure test, it is a problem as well.
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DivineStripe
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Thank you for your response. The leak and vacuum tests were entirely satisfactory. I attempted to manually engage the clutch using ISTA, but was unsuccessful; nevertheless, I did not do any more testing. There are no fault codes in ISTA pertaining to the auxiliary fan. Attempted to activate the fan using ISTA without success. I will attempt to contact INPA to see if I get any more findings. I am uncertain if ISTA is the best suitable tool for doing such activities on the E53.
Disconnect the connection from the compressor and attach a 21w test bulb, such as a tail light bulb. When the engine is operational and the air conditioning is activated, if the indicator illuminates, it signifies that the system is requesting the clutch to engage, indicating that all other components are functioning properly while the clutch is defective. An LED test light may not be effective in this scenario, as it may register some voltage but may not provide sufficient wattage to engage the clutch. Aside from the fan or the pressure switch, fault codes for an air conditioning system are few, necessitating manual diagnosis.
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DivineStripe
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I conducted another test using INPA this time. Attempted to activate the e-blower on the DME without success; it is uncertain if this pertains to the auxiliary fan. I saw that the climate module has an option to reverse the compressor's deactivation. The ECU seems to have disabled the compressor, leading me to suspect that the clutch may be defective. Additionally, there is a singular issue in the climate ECU pertaining to the compressor's clutch. Are you familiar with the procedure to activate the auxiliary fan using INPA? Is there anything more that I have overlooked? Thank you in advance
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matthewlightburn
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No error code when my fan malfunctioned.
The clutch is the last component in the system, with the DME determining whether it engages or not. If a malfunction occurs prior reaching the clutch, it is deactivated to safeguard the most costly component (compressor). This issue cannot be diagnosed alone with a scanner; it is necessary to connect the system to a machine or gauge to assess the pressures inside it. Examine for excessively low or high pressure on both the low-pressure and high-pressure sides, and inspect for leaks, among other issues. If you are certain the gas is accurate, then verify all other components, including sensors, etc. I would not recommend tampering with the gas system due to the high pressures involved; a certification is required for work on it for a reason. I am uncertain if applying 12V momentarily to the fan connection would activate the fan, since I believe the controller is integrated inside the fan itself.
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DivineStripe
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A trained technician should examine it. I will inform you promptly upon securing an appointment.
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craigstomer
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As recommended, measure the resistance of the magnetic clutch coil. Attempt to ignite it with direct voltage.
INPA should effectively activate the electric fan via the DDE. The fan receives a constant voltage supply and an activating PWM signal from the DDE; hence, a PWM signal generator is required for manual testing reasons. You can certainly measure the voltage and ground on the fan connection located by the radiator shroud.
INPA should effectively activate the electric fan via the DDE. The fan receives a constant voltage supply and an activating PWM signal from the DDE; hence, a PWM signal generator is required for manual testing reasons. You can certainly measure the voltage and ground on the fan connection located by the radiator shroud.