Continuity between +ve and -ve battery leads

Paul_S

Club Member
Is this normal...?!

I've not ever know my 240Z with a battery fitted and as a test before installing one I thought I would check continuity between the earth and positive leads - the plan is to test for a short before I put the battery on.

My tester squealed away telling me there was continuity between the two so I investigated further. It does it when I pull the key out of the ignition, and even when I disconnect all the fuses in the fuse box.

I suppose my question is - do I have a wiring problem or am I being stupid and something like the alternator will always cause this?

Thanks :)
 

johnymd

Club Member
On the ignition barrel there are a pair on connectors. I think these are for the buzzer to warn if the key is left in the ignition with it turned off. As far as I'm aware, this is the only thing that changes when the key is removed from the barrel so worth investigating.
 

Paul_S

Club Member
On the ignition barrel there are a pair on connectors. I think these are for the buzzer to warn if the key is left in the ignition with it turned off. As far as I'm aware, this is the only thing that changes when the key is removed from the barrel so worth investigating.
Ah, thank you. I will check that out. I fear there is a short somewhere but I'm just going through the 'obvious' things to check first.
 

jonbills

Membership Secretary
Site Administrator
Isn’t the cig lighter live with the ign off? I’m sure mine is and I have a USB adapter in it, so would expect continuity between the battery terminals.
I’d be more inclined to put the battery in and measure the current drain when it’s all off.
Do you have a reason to be concerned about attaching the battery?
 

Paul_S

Club Member
I've just been playing with the car and found the fault - just a simple dodgy unused cable from some modification in the car's previous life.

Isn’t the cig lighter live with the ign off? I’m sure mine is and I have a USB adapter in it, so would expect continuity between the battery terminals.
I’d be more inclined to put the battery in and measure the current drain when it’s all off.
Do you have a reason to be concerned about attaching the battery?

Thanks for you help :)

It's a good question about my concern about attaching the battery - I have no reason to believe there would be a problem but the car had been parked up and tinkered with for 10 years before I took ownership and I'm taking the approach to assume nothing and check everything.

I'm being over-cautious because I had a nightmare about it bursting into a fireball when I connected it! :eek:
 

Jimbo

1978 260z in yellow
Club Member
in mine i seem to remember the voltmeter being always live as well, I'm sure i asked the question before if its supposed to always be live?
 
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