warning coolant visit workshop - p201f-002
facts:
1. my car recently got this error . it has m271 engine.
2. i have MBII diagnostic tool and it say i have DTC = P201F-002.
"m4/7 (engine and ac electric suction fan with integrated control). short circuit to ground open circuit wiring.
3. the error is intermittent, somethimes there is error sometimes none. error can appear even from cold start or even if engine already warmed up.
4. so far, i dont get this error after start(idle or driving).
5. if for example upon start, i got the error and continue driving, the fan will not turn on, it goes beyond 80 degees Celsius. buf if you turn off the engine and be lucky not to get the error, the fan will move!
6.fan relay in the engine bay already inspected and replace with new one
7. coolant temperature sensor is ok on my opinion because i see on dashboard that it is rising
8. cleaned connector of fan assembly, no carbon deposit or sign of meltdown.
* i tried unplugging the fan module , tried starting the car and so far i dont get the DTC, im still observing if it will be consistent without throwing error(at least for the purpose of isolaton)
what could be the problem? any recommendation on what to check?
10. i tried with aircon left at auto then turn off the engine , i got p20f1.
11. late this night , i got srs error, my MBII cannot detect airbag, front , rear , passenger sam etc. ECU on the other hand was ok , MBII can still communicate. I cleaned the connector of CGW, then replug. All SAM reachable again. so i clear all DTC. restatrt the car, fine no DTC. restart again the car (aircon l
9. 2/26 starting car couple of times with aircon off, the onces started , turn on aircon, so far i did not encounter error
10. i tried with aircon left at auto then turn off the engine , i got p20f1.
11. late this night , i got srs error, my MBII cannot detect airbag, front , rear , passenger sam etc. ECU on the other hand was ok , MBII can still communicate. I cleaned the connector of CGW, then replug. All SAM reachable again. so i clear all DTC. restatrt the car, fine no DTC. restart again the car (aircon left auto before turning off) , no P201F. I'll try again tommorrow if output is repeatable.
10. 2/27-2/28 - since i replugged the CGW, the result now more consistent. from cold start (aircon set to 0), p201f consistent. I tried clearing the code while enging running but it keep coming back. i did many restart till 80 degrees celcius;
11. i pulled out the fan plug while engine running, clear the code(sucessful) , reinsert the fan module, rescan again, no error......restart the car ,no error. why it becomes ok when i replugged the fan connector? ill do futher scenario tomorrow.
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i even though that it is related to battery, so to isolate concern on battery , i put the car on battery tender . yesterday, i get a consecutive success gradually increasing interval between restart 30mins, 1 hour, 3 hours , 4 hours then i got the error again! so this isolation was done without starting the car, touching, wiggline the wires and so on.
since im suspecting connector as well , i disconnect the ECU, then do restart interval again( i have done 8 hour interval). so far, no error, still observing
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