iceman Posted September 22, 2019 Report Share Posted September 22, 2019 Hi, Trying to work out how to temporarily disable the engine fan on engine start to lower overall battery current draw when cranking. I have start position wired through a DI channel and fan control through an Aux as usual. I'm hoping it can be accomplished using a virtual GP channel from there but cannot quite get the conditions/switch logic right.....Am I on the right track? Some advice would be appreciated. Cheers. Quote Link to comment Share on other sites More sharing options...
cj Posted September 22, 2019 Report Share Posted September 22, 2019 have you configure the output as GP out or engine fan? If its GP out just set a condition for RPM > 500 or something. If its engine fan, it should be temp controlled, at which point, whats the chance that your coolant temp is 95-100 or whatever the switchon temp will be, when the engine is either cold or freshly stalled after running? Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 22, 2019 Report Share Posted September 22, 2019 I’m pretty sure the default fan control strategy will not enable the fan aux when the engine is not running, you should not have to change anything. Quote Link to comment Share on other sites More sharing options...
iceman Posted September 23, 2019 Author Report Share Posted September 23, 2019 Hi Adam, After looking at this again, I believe it does as per the highlighted help file info below. Presumably you would need "hold power" configured to keep the ECU alive after key off to get the fan to run for a short configured time period after shutdown. I don't have hold power set up so I think I could achieve the fan cut during cranking by just entering 0 secs in the time out value as power will be on to the ECU during start. The only possible issue would be does the ECU see RPM while only cranking with ignition/ECU on as it is only a zero RPM time lockout and not an actual RPM level lockout? I'm not in a position to immediately try this myself. Cheers. Engine Fan Settings: · Non Driven Speed Lockout - The Non Driven wheel speed above which engine fan and condenser fan operation will disable. This setting has a hysteresis of 5 kph. If set to 0.0 kph the lockout will be ignored. If set too low the engine could overheat. · RPM Zero Timeout - The amount of time the Engine Fan will run for once the engine speed is zero. It is useful to set this timer so the system will continue cooling, but not flatten the vehicles battery. This timer is only active while the ECU has power, if the ignition key kills the engine and turns off power to the ECU then the timer will not run. · Engine Fan X Temperature - The temperature ECT must reach for Engine Fan X to turn ON. · Engine Fan X Hysteresis - The number of degrees ECT must decrease below the Engine Fan X Temperature before the Engine Fan X will turn OFF. It is required to eliminate short fan cycles. · Engine Fan X on with AC - If set to Yes Engine Fan X will turn ON one second after AC Clutch activates. The one second delay is to spread the increased engine load from the AC Clutch and condenser fan turning ON. Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 23, 2019 Report Share Posted September 23, 2019 The fan won’t turn on until the “on” temperature is exceeded and engine RPM is above 400. Quote Link to comment Share on other sites More sharing options...
iceman Posted September 23, 2019 Author Report Share Posted September 23, 2019 Excellent. Thanks Adam. Quote Link to comment Share on other sites More sharing options...
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