How do you test the OEM battery charger to see if it works?


JCO1966

JCO1966

GT Owner
Mark II Lifetime
Jul 22, 2006
183
Greenville SC
Hey guys. I have two GTs and I am always replacing batteries in one of them. I drive both cars at least once a month and keep them on the OEM battery charges 24/7. The car I am having problems with I just replaced the battery (OEM optima) about a year ago. Recently with. Bad weather and the holidays I did not drive it for a couple months. When I went to drive it a few days ago the battery is completely dead. I put a battery tender trickle charger directly on the battery for 7 days and it has not brought it back! So I have decided to get the point plug for the battery tender and use it now so I will know if it is charging or not. The most important thing is I want to check the OEM battery charger to see if it is working or not so I know what the problem has been. I checked the ground to the frame and it is tight. I did not take it off yet to check for corrosion! The cars stay in a climate controlled garage. I also checked the power pint fuse and it is ok. Thanks for the help guys! Chad
 
It's an omen. Get rid of that one! I'll take it. Lol. Keith from Michigan.
 
Disconnect the positive battery terminal, put a voltmeter across them, and plug in the charger. You should see 12V (or thereabouts) appear at the positive terminal. If not check the fuse for the accessory plug (or plug something into it to see if you get power). If the fuse is OK the charger isn't...

This might not be definitive. The charger may be able to supply voltage but not enough current when under load but it will eliminate a totally broken unit.
 
A tight ground bolt to the frame is not sufficient evidence of a good ground if you are having charging problems. I had a tight bolt a couple of years ago and I still got stuck with a bad ground. Recleaning the connection solved my problem immediately. (For good measure I also added a nearby, redundant ground cable.) Even if that is not the source of your battery problem it's an easy way to eliminate the possiblity. BTW, I use a C-TEK charger for the GT and I'm still on the OEM battery (knock on carbon fiber).

Howard
 
Thanks everyone!
 
My two cents is replace the stock one with the one sold by CoolTech. Nota4re on this forum is the owner. I just did this and couldn't be happier. You know the CoolTech setup is working because it has colored LED lights that tell you what it is doing. CoolTech shipped my unit the day I ordered it which was much appreciated.

Craig
 
OEM charger is warm to touch when plugged in and cigarette charger in


Remover the ground strap and sand the tapped washer / threads insert (roll up sand paper) and use dialectric grease and tighten bolt

After 4 years my OEM acted up once before i did above; after battery went for another 2 years and still cranked when changed

OPTIMAs can last 6-7 yrs

That biggest risk with chargers is NOT using them....the OEM is hard to beat if plugged in
 
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...or a Ctek...which is also an excellent unit and has indication of charging.
 
Thanks guys I have a couple extra battery tender juniors so I ordered the cigarette adaptor. I will switch both cars over to them and clean the grounds. I read somewhere on the forum that there is one kind of grease to use and one kind not to on the ground strap parts? Does anyone remember? Thanks for the help! Chad
 
Ok we need someone to come up with a "led splice in line kit" that tells us it is working.
 
tpraceman said:
Ok we need someone to come up with a "led splice in line kit" that tells us it is working.
Click to expand...

It's called a Deltran charger. Sells for $29 at Advanced Auto..............
 
Ctek makes a red-yellow-green status meter- cigarette plug that tells u state of ur whole system

Saw it in Octane this month

http://smartercharger.com/products/accessories-cat/ctek-comfort-indicator-pigtail/
 
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Similar to Noco's Genius system. I've been using the G7200 at the ski area to maintain the charge on the deep-cycle battery used for the horse-gate controller used in dual elimination races, and I'm very satisfied with it. I plan to get one to maintain the battery on my boat.

http://www.geniuschargers.com/G7200

http://www.geniuschargers.com/GC015

I use Kendall'a ChargePort float charger on the GT.

http://www.cooltechllc.com/ford/gt_chargeport_gt_float_charger_kit.shtml
 
as others have said, buy a Deltran (or other). I have several Deltrans. You can find them cheap on amazon. Also you gont have to buy the "gel cell" version. I talked to deltran at SEMA a couple years ago, this sticker was only done for BMW to sell the chargers at the parts counter. The gell cell version is the same as a regular. I just plug into the "cigarette lighter" / Power port, and just shut the door one click on the wire. Works for me for the last 6+ years.
 
I just put a voltmeter on mine and got an initial reading of 17.4 volts. I guess it's doing something.
 
The problem with these dry cell batteries is that they can test well in short bursts. A deep cycle test is necessary to properly tell if these batteries are still fully operational (insert Death Star music here). I have heard mixed reviews on the factory charger unit, but a “high end” trickle charger is not overly-expensive and you can buy one that will keep several batteries maintained (if you have other cars or motorcycles).
 
Straight from the mouth of the guy whose car has been in parts for how many years? So how have you kept your battery charged in this interim Mark?
 
fjpikul said:
Straight from the mouth of the guy whose car has been in parts for how many years? So how have you kept your battery charged in this interim Mark?
Click to expand...

With all of the other parts Mark is buying, an new battery isn't material.
 
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