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Battery drain TNS relay

Old Oct 24, 2016 | 06:02 PM
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Default Battery drain TNS relay

hey wondering if anyone has any suggestions on solving my battery drain issue. The relay is always reading 12v even if the car is completely off, keys out and everything. The fuses are also reading at 12v (tail, stop, hazard). The tail lights are not on and not showing any voltage. The battery dies overnight, and ive had to just disconnect the battery whenever i park. Any suggestions of what else i should do would be super helpful. Ive already replaced the TNS relay.
Old Oct 24, 2016 | 10:24 PM
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Just checked my wiring diagram, the TNS relay is suppose to see voltage all the time . If the lights arent
on , its normal . Start looking else where. Charge voltage , load test the battery , start with the basics. Fred B
Old Oct 25, 2016 | 01:09 PM
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All your lights work regardless if the ignition is on or off so the fuses will always have 12v at them. You need to do something like this How to Find a Parasitic Battery Drain: 9 Steps . Another option is testing for current drop across the fuses, if you google there's a chart that converts fuse size voltage drop to current draw., Just make sure to to disconnect your door switch so it's not reading that your door is open while testing with the door open. Either way should work, I like to see what the draw is and then doing the voltage drop across fuses, it's quicker for me.
Old Oct 25, 2016 | 04:31 PM
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figured it out, the third brake light was stuck on, bulb was dead. not sure why it stuck on but i think i can figure it out from here, thanks guys
Old Oct 25, 2016 | 06:14 PM
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If the bulb was dead there should be no draw because the circuit would not be complete.


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