Battery drain.

Barry.b

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Hi guys
My September 1973 built 3.0 RHD CSi is using power from the battery when nothing is turned on and without the keys in the ignition.
As in with no interior lights connected and with the power lead disconnected from the clock as soon as I connect the leads onto the battery, I can hear a click somewhere in the car and I can see a small “connection spark “ when I touch the leads to the battery.
Is that normal ?
Also my front electric windows work without the key in the ignition
Is that normal ??
 
Your window motors are energized when you open the door via a latching relay. If you don’t have the plastic plug on your door to close the dome light switch your relay will drain the battery in five days, 25 milliamps if I recall. This is a feature of coupes with the improved motors
 
Hi Chris
Thanks for the info
I would Never have figured that one out !

My alternator/ generator is a bit lazy , so every milliamp makes a difference at the moment.
I sent my alternator in to get rebuilt early last week and got it back Thursday night. I refitted it , but unfortunately she’s only making 12.6 volts and when the car is switched off and the key’s removed the red “L” light stays illuminated.
So I was supposed to go back today and get a new alternator fitted and my voltage regulator bypassed. But the sun has FINALLY started to shine, so I’m not taking my car off the road just yet :) :)
 
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Howdy, Barry.

Do you have a DC current clamp handy? (example: https://www.amazon.com/dp/B09LGY1YY...47c999026&sp_csd=d2lkZ2V0TmFtZT1zcF9kZXRhaWwy) It's a great tool for these sorts of things, as you can look for current flows on different harness paths with the car off. If you don't, then the next step is to pull the fuses and the power lead, and connect them back in one at a time, checking for the draw you mentioned to show up. That at least gives you some idea what branch of the harness contains your draw, and you can start checking individual devices on that circuit.
 
Try disconnecting your hazard switch. This switch has both BATT and ACC connections. If it shorts internally the ACC bus will be activated without the key being on
 
as soon as I connect the leads onto the battery, I can hear a click somewhere in the car and I can see a small “connection spark “ when I touch the leads to the battery.....and when the car is switched off and the key’s removed the red “L” light stays illuminated.
No, none of that is normal. It sounds like your ignition circuit is always "ON", sending current to the load shedding relay (that click you hear when you connect the battery) as well as to the "L" light. ScottAndrews' theory that the hazard switch is the problem could be correct. But somehow, your car is always on. It would be interesting to take a voltage meter to various points on the car when the battery is connected. Is the coil "+" showing 12V? Do the gauges come to life?
 
If your door is open, when you connect the battery, you will get that small spark, cause you are energizing the relay for the windows
 
No, none of that is normal. It sounds like your ignition circuit is always "ON", sending current to the load shedding relay (that click you hear when you connect the battery) as well as to the "L" light. ScottAndrews' theory that the hazard switch is the problem could be correct. But somehow, your car is always on. It would be interesting to take a voltage meter to various points on the car when the battery is connected. Is the coil "+" showing 12V? Do the gauges come to life?
It’s a simple test. Unplug the hazard switch, and try your battery connect test. No spark and you have found the culprit
 
If you need to chase further...

Connect the Meter in Series with your Battery (route all current through your multi-meter)
  • Disconnect the negative battery cable.
  • Connect the red lead to the battery post, and the black lead to the cable you removed.
Read the Current Draw: Start with a high amp setting 10A or higher & switch to mA if needed

Isolate the circuit fuse by fuse, When the current drops significantly, you’ve found the circuit, then you switch to tracing the wiring and circuit components to find the cause for the draw
 
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