Can’t fix this fan running!!!!
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AudiWorld Newcomer
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Can’t fix this fan running!!!!
Hey guys I need some help. Bought a 2013 Audi a6 Quattro with 57k miles. About a week after purchase my fan came on with the light throwing a coolant system code. Well since this, I have gotten a thermostat( previously replaced twice before purchase) water pump, fixed all the wiring, fan relay, coolant senser, then Audi said to take out the first thermostat and put in a oem.. so Audi has since put in a new thermostat.. finally thought it was fixed and the engine light came on again as well as the fan not even 200 miles later. I have spent close to 5000 in repairs any help!!!??
AudiWorld Member
Joined: May 2024
Posts: 116
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From: SARASOTA, FL
What's the code? What is the car fussing about? What is your engine coolant temp when the fans come on? You also mentioned 'fixed all the wiring.' What does this mean? Are you suggesting that there were confirmed wiring issues found then fixed?
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The code it’s throwing is P2181. Since the new thermostat was installed, the engine now heats up to normal operating temperature, but the cooling fan runs on high constantly and it’s still throwing the same code. When this first started, I took the vehicle to a German auto repair shop that replaced the thermostat along with the water pump housing unit. The part they installed was not OEM, and less than 75 miles later the fan started running at full blast, the check engine light came on, and it was throwing the same P2181 code again.
After that, I took it to the Audi dealership. They initially repaired the coolant sensor wiring and replaced the coolant temperature sensor, but they were still unable to determine the issue. Audi then consulted their engineers, who advised that the thermostat needed to be replaced with an OEM unit. Audi replaced the thermostat with an OEM part and corrected the previously spliced wiring. They also replaced the thermostat again, along with the coolant sensor and water pump, yet the issue persists with the same code and constant high-speed fan operation.
After that, I took it to the Audi dealership. They initially repaired the coolant sensor wiring and replaced the coolant temperature sensor, but they were still unable to determine the issue. Audi then consulted their engineers, who advised that the thermostat needed to be replaced with an OEM unit. Audi replaced the thermostat with an OEM part and corrected the previously spliced wiring. They also replaced the thermostat again, along with the coolant sensor and water pump, yet the issue persists with the same code and constant high-speed fan operation.
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AudiWorld Super User
Joined: Sep 2004
Posts: 3,358
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From: BC, Canada
So your issue is the fans always running? Maybe the fan relay is getting "sticky" Sometimes the contacts inside a relay can weld themselves closed, maybe yours is close to this point and starting to stick closed??
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AudiWorld Member
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From: SARASOTA, FL
Any water intrusion where the ECU is? I heard that's a common problem. If you are equipped/capable, I'd start with the live data: Compare commanded vs. actual fan speed, monitor G62 temp readings for glitches/jumps. You may be looking at a failing fan control module which is on the fan assembly itself.
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