Mystery wire in trunk...?
#1
Mystery wire in trunk...?
When replacing the battery, I noticed a wire with a connector that is hanging loose from the harness. It looks like it was from the factory. It is small, white w/ blue, and has a female-spade crimp terminal. It is near the positive side of the battery.
Anyone know?
Anyone know?
#4
#6
Here is how it work:
this "relay"got on top of the + side of the battery
The + battery cable connect then to the relay
The small blue/white wire connect to the negative side of the relay coil
The + side of the relay coil is connected to the + side of the battery.
The small wire is supplied ground from the BCM to energize the coil and close the circuit between the battery + and the positive battery cable
When the car go to "sleep", the ground feed to the small wire is interrupted, and the coil open the circuit
Now, how do they re-power the coil to start the car beside removing the relay?
There is another connector on the relay that supply 12v all the time but not sure what it is used for
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ericjansen (03-09-2017)
#7
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ericjansen (03-09-2017)
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#8
Nori:
This PDF is not for an X308 but rather for an X350
The relay look exactly the same but not the wiring.
The X308 only has the auxiliary connector "D" (the little blue/white wire) and not the by-pass feed connector"B"
As I mentioned in my post, the relay on the X308 has the connector for "B" but no car harness/wiring going to it
This PDF is not for an X308 but rather for an X350
The relay look exactly the same but not the wiring.
The X308 only has the auxiliary connector "D" (the little blue/white wire) and not the by-pass feed connector"B"
As I mentioned in my post, the relay on the X308 has the connector for "B" but no car harness/wiring going to it
#9
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#10
No problem, This, and Luc's post give a perfect explanation of how it works.
Always wondered, each and every time the question on the mysterious trunk wire came up.
Now I wonder if refitting such isolator is a useful addition for those of us who use the car only every now and then ... seems a perfect automated device for those of us who are not hooking things up to a tender.
Always wondered, each and every time the question on the mysterious trunk wire came up.
Now I wonder if refitting such isolator is a useful addition for those of us who use the car only every now and then ... seems a perfect automated device for those of us who are not hooking things up to a tender.
#11
#13
These items have positive reviews from the UK classic car world. Maybe something like that would suit you Eric?
Products Archive - Battery Brain
Products Archive - Battery Brain
#14
#15
Well I've seen these and similar systems work well for a number of years now.
Personally I'd just buy a high quality battery and leave it to it. If you can't leave your car a month without it going flat, you've got either a crap battery or another issue. I use Varta batteries, which Jaguar supply OEM, and never had an issue with leaving standing. My Triumph hadn't been started since November but the other day she fired first time, as did the Audi Coupe which had also sat over winter. Both on Varta.
Personally I'd just buy a high quality battery and leave it to it. If you can't leave your car a month without it going flat, you've got either a crap battery or another issue. I use Varta batteries, which Jaguar supply OEM, and never had an issue with leaving standing. My Triumph hadn't been started since November but the other day she fired first time, as did the Audi Coupe which had also sat over winter. Both on Varta.
#16