Is there a circuit that is only on when the engine is on? I tested all the fuses in the left and right fuse compartments and they all tested active with the car ignition on but the engine off. I’m looking for a fuse that is active only when the engine is running. 2017 Exec. Thanks.
Is there a circuit that is only on when the engine is running?
GATouareg
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Is there a circuit that is only on when the engine is on? I tested all the fuses in the left and right fuse compartments and they all tested active with the car ignition on but the engine off. I’m looking for a fuse that is active only when the engine is running. 2017 Exec. Thanks.
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I'm not certain, but I believe the inverter gets an engine running signal via the alternator. You could tap into that with a relay to provide power.
What is it your trying to do?
What is it your trying to do?
Thanks. I am installing a subwooofer and I only want it to power up when the engine is running. Currently, the radio turns on when the car is on before staring the engine.
@GATouareg -- Check the wiring diagrams for relays J17 (Fuel Pump) or J643 (Fuel Delivery). I would expect that these are energized only with the engine running, based on a output from ECM J623. If you find the operating condition (that is, presence of +12V) sufficient for your subwoofer application, use this to operate a separate relay to power your subwoofer from a Terminal 30 (starter battery) source. --g
In my 2017, the outlets are live when the car is on even before the engine/alternator starts spinning. I am looking for a circuit that is live only after the engine/alternator starts spinning.
Ah, sorry, misunderstood the goal. Clearly my pre-caffeine reading comprehension is low.
@GATouareg -- Your specific requirement that the "alternator be spinning" suggests that the measured Terminal 30 voltage be greater than starter battery quiescent voltage (say, 12.6V nominally) for your subwoofer to be powered on.
Consider something like this: Voltage Detection Module Relay Switch Charging Discharge Monitoring Protection | eBay
where V1 is set to 12.9 and the device is operated in "fixed-point monitoring" mode. --g
Consider something like this: Voltage Detection Module Relay Switch Charging Discharge Monitoring Protection | eBay
where V1 is set to 12.9 and the device is operated in "fixed-point monitoring" mode. --g
That looks it could work and its the right price. Thanks.
Will that work with a smart alternator, which drops the voltage frequently to reduce fuel consumption? It's an issue with many cars. Touareg with factory-fit towbar gets round this by using canbus to detect the presence of a trailer (being plugged in) and keeps the voltage higher to keep a caravan fridge running.
Thanks for the suggestions. I decided to connect the remote subwoofer turn-on wire to a terminal 15 circuit which is off when the car is off. I will need to remember to not play the radio if I have ignition on without the motor running, or turn down the subwoofer.
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Just put the amp on line on a switch, if you want the sub on just flick the switch.
Honestly I'd just put the a switched circuit and it will be fine. I've installed a few subs and unless your running SPL type monsters your not going to drain the battery provided you don't run it for more 30 minutes with the engine off.
My 12 inch uses the 12v cig lighter circuit as it's switched and only draws a few milli Amps.
Never had an issue
Honestly I'd just put the a switched circuit and it will be fine. I've installed a few subs and unless your running SPL type monsters your not going to drain the battery provided you don't run it for more 30 minutes with the engine off.
My 12 inch uses the 12v cig lighter circuit as it's switched and only draws a few milli Amps.
Never had an issue
Thanks, that is what I ended up doing (I used a switched fuse on the left side as the amp connections are on the left side).
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