Grounding a Battery Tender
Safety Car
Joined: Feb 2004
Posts: 3,802
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From: monroeville pa
St. Jude Donor '04-'05-'06-'07-'08-'09-'10-'11-'12-'13
Originally Posted by vetdude
The instructions that come with the Battery Tender Plus specifically state, do NOT connect negative clip to anything but the negative post on the battery. 
Safety Car
Joined: Oct 2000
Posts: 4,949
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From: Monticello MN
Originally Posted by wwashing
Well, of course the instructions with my automatic charger are different. My charger (Griot's Garage Automatic Charger) says "connect the Negative (BLACK) clamp to the vehicle chassis, heavy guage metal part of the frame, or engine block, away from the battery". I connect mine to that metal tab that sticks up from the water pump.
The reason this is suggested is that there is a chance that connecting the negative terminal could result in a spark. And, since vented battries could be releasing flamable gases, the safe route for the manufacturer is to suggest attaching the ground away from the battery.
The reason this is suggested is that there is a chance that connecting the negative terminal could result in a spark. And, since vented battries could be releasing flamable gases, the safe route for the manufacturer is to suggest attaching the ground away from the battery.
Ed
Racer
Joined: Jul 2001
Posts: 455
Likes: 2
From: manahawkin,nj
Ground mine to the bottom of the rubber hood bumper O terminal bolted on there. the positive I bolt to the hot terminal that comes off the side of the fuse box. This way you can simply plug in the tender to the wire harness that comes with the tender.
Jerry
Jerry
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Joined: Oct 2004
Posts: 61
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From: Elk Grove Village Illinois
I bought a trickle charger from Sears and the instructions said to ground the negative clip to the car's chassis. I hooked the charger that way, got a green light indicating the battery was fully charged, and went on with my businesss.
A couple of months later I tried to open the car doors with my FOB and the battery was completely dead, but the green light was still on. It wasn't until I hooked the negative (black) clip of the battery charger to the negative battery post that the battery was charging. Once I did this the amber light on the charger went on indicating the battery needed charging.
In my experience the battery charger clips should be hooked directly to the battery.
A couple of months later I tried to open the car doors with my FOB and the battery was completely dead, but the green light was still on. It wasn't until I hooked the negative (black) clip of the battery charger to the negative battery post that the battery was charging. Once I did this the amber light on the charger went on indicating the battery needed charging.
In my experience the battery charger clips should be hooked directly to the battery.
