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Discussion Starter #1
I've a first gen Leaf24 (2012) and have noticed it makes a 'tick-tock' relay-like sound when parked. This repeats, i've not measured interval times, but would guess maybe once or twice every half hour. When the car is parked in my garage i've noticed the 'tick-tock' when i'm working on other things at my workbench.

Car is turned off, not connected to charger (most of the time). The 12v battery doesn't seem to run down, though longest i've left it is a week.

I'm curious to know whether all/any/some other Leafs do this ? Does anyone know what is making the tick-tock ? (suggestions about deathwatch beetle not appreciated...)
 

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30KW Tekna (2017)
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I have a 30KW Tekna and have also noticed weird sounds from the car when its been off and Ive been sat in it waiting for people etc.

I always think the sounds come from more the middle / rear of the car.

I have always assumed its doing "electric car stuff", I mean basically we drive big computers so I always thought its maintaining itself!
 

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basically we drive big computers
Well, we don't really. With all this drive by wire stuff, we just just sort of suggest what we'd like the car do and it chooses whether to comply or not... for now.
 

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Discussion Starter #5
Topping up the 12v, I wonder?
I think that might be one of the 'less likely' reasons (?). Only because keeping the 12v properly charged seems to be a shortcoming of the Leaf - at least for some of them.

AFAIK, the only thing that'd need to be working when the car is turned off is the alarm - any other stuff running in the background might drain the (puny) 12v battery.

Main battery cell balancing only happens at the end of a slow/fast charge - so it can't be that (?).

I suppose it might be very excited electrons jumping around expectantly; eager to find the next bypass on-ramp :)
 

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I have noticed my 24kWh LEAF also make an intermittent tick tock sound and one of the 3 blue charging indicators flashes at the same time ( when disconnected from the charger) I would like to know if this is a normal characteristic of a static LEAF?
 

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Depends which light.
One will flash if its charging the 12v battery.

Another will flash if the park heating is activated.

They all flash one at a time if a timer is activated.
 

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The "Tick-Tock" noises are contactors. In other words relays. Remeber when indicator tick-tock was the actual mechanical noise of the relays passing the signals? Well, the Leaf (and all EVs) have much bigger contactors that isolate the HV battery. Whenever you plug a LEAF in to charge you will hear the "clunk-clunk" of contactors connecting the HV battery to the on-board charger - the contactors can connect and disconnect various items from the HV bus (eg traction motor, on board charger, 12V DC-DC, Rapid Charge input, battery), and there are certain combinations that are not valid (for example, rapid charge input and traction motor would never be simultaneously connected (possible use case - in-flight refuelling!)).

I have noticed my 24kWh LEAF also make an intermittent tick tock sound and one of the 3 blue charging indicators flashes at the same time ( when disconnected from the charger) I would like to know if this is a normal characteristic of a static LEAF?
Yes. Completely normal. When just the 3rd (ie highest charge state, passenger side) charger light is flashing when the car is not plugged in that is showing that the car is charging the 12V from the HV pack.

I think that might be one of the 'less likely' reasons (?). Only because keeping the 12v properly charged seems to be a shortcoming of the Leaf - at least for some of them.
The Leaf has one major glaring shortcoming of its 12V battery handling in my experience, which is that the 12V will not charge if the car is left plugged into AC and has finished charging the main battery (whether to 100% or 80% if set so on a 24). What happens then is people go on holiday for 2 weeks, leave the car plugged in expecting it to take care of itself and come back to find the 12V dead, whereas if they had left it unplugged then the 12V would be fine and they'd have lost only a couple of % of the HV charge. We left our Leaf for 3 weeks while on holiday, unplugged at 63% charge, still at 61% when we returned home and no 12V problems.

The problem stems from mantras like "always be charging" and people reading that Tesla recommend to leave their cars plugged in (which they do) and expecting that what applies to a Tesla also applies to a Leaf.

The other 12V shortcomings of the Leaf (small float range, small battery) are largely irrelevant if the 12V is able to tend itself from the HV battery. It's just that having an AC charger set on a timer for E7 prevents the 12V from tending itself.

AFAIK, the only thing that'd need to be working when the car is turned off is the alarm - any other stuff running in the background might drain the (puny) 12v battery.
Communications has to be running for app access. The Keyless entry system must be "listening" for the key.

Main battery cell balancing only happens at the end of a slow/fast charge - so it can't be that (?).
Correct. Balancing is switched using tiny MOSFETs that are part of an ASIC in the Leaf BMS. They make no noise.
 

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Discussion Starter #9
Many thanks - tho i've never witnessed the left-side single blue/dash/charging light flashing - indicating 12V battery charging. But, i put in a new 12V battery a year ago - and don't pay much attention...

While i get that the tick tock is coming from a relay; i've still not understood what car activity (parked, not plugged in or charging) would need a regular relay activation - relatively frequently ? I'd doubt its the keyless entry system - this would be solid state (?) not something involving a relay (and i've had other cars with keyless that didn't tick-tock).

Obvs, the tick-tock feature was an extra included with the 'any colour as long as it's electric blue' paint option. Or not.
 
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