You guys were all right. This morning light is steady green, Tender is just barely warm so all is well. This forum is great!
Battery Tender Issues?
Thread Starter
Le Mans Master
Joined: Sep 2012
Posts: 7,146
Likes: 1,940
From: Hagerstown MD
St. Jude Donor '15-'16,'18
Battery Tender Issues?
I won't be driving my car for several days so I decided to connect my Battery Tender to see how it responded. Since I had driven the car I expected that the tender would show a green light when I plugged it in. Instead it was a steady red light which means the battery is being charged. Even after several hours it is still red, I would have thought it would at least have gone to blinking green showing that the battery is almost fully charged. I am going to to check again tomorrow morning but if it isn't a steady green light I'm going to disconnect it. I never had this issue on any of my other cars. I am using the rear socket in the car. Any idea if this is normal?
Team Owner
Joined: Sep 2005
Posts: 20,352
Likes: 568
From: Ventura County, Calif
Pretty typical.
My C6 is like that. I can drive it for several hours, come home and plug in the Battery Tender and it will show charging for 8 hours or more.
The alternators in these cars don't put out enough at low RPM to keep the battery fully charged. Of course I'm only assuming the C7 is similar.
My C6 is like that. I can drive it for several hours, come home and plug in the Battery Tender and it will show charging for 8 hours or more.
The alternators in these cars don't put out enough at low RPM to keep the battery fully charged. Of course I'm only assuming the C7 is similar.
Intermediate
Joined: May 2015
Posts: 32
Likes: 2
From: Lake Norman North Carolina
Mine was like that the first nite I plugged it in . I got a little nervous at bedtime , the light wasn't green & the unit was pretty hot. I moved it away from anything that might have caused a fire. (Just in case) Next day was all good. & seemed to work normal , the rest of the times, so far.
Thread Starter
Le Mans Master
Joined: Sep 2012
Posts: 7,146
Likes: 1,940
From: Hagerstown MD
St. Jude Donor '15-'16,'18
Safety Car
Joined: Oct 2014
Posts: 3,543
Likes: 854
Randall:
I have my C7 connected to a CTEK MUS4.3....8 step smartcharger. It is connected 100% of the time when not driving the C7. Even after driving the car, the CTEK takes a few hours (1-2) for the LED's on the CTEK MUS 4.3 to cycle through the charging process. These chargers deliver a very slow and low charge. There is never a fear of a quick overcharging when using these devices.
Other C7 owners might did disagree, but the with the mass amount of electronics in the cars they do drain the battery.
Your charge is normal and most likely you will see a charged battery in the morning.
Instead of using the cigarette adapter in the hatch, I have my CTEK MUS 4.3 wired directly to the 10mm battery posts for a direct charge.
I have my C7 connected to a CTEK MUS4.3....8 step smartcharger. It is connected 100% of the time when not driving the C7. Even after driving the car, the CTEK takes a few hours (1-2) for the LED's on the CTEK MUS 4.3 to cycle through the charging process. These chargers deliver a very slow and low charge. There is never a fear of a quick overcharging when using these devices.
Other C7 owners might did disagree, but the with the mass amount of electronics in the cars they do drain the battery.
Your charge is normal and most likely you will see a charged battery in the morning.
Instead of using the cigarette adapter in the hatch, I have my CTEK MUS 4.3 wired directly to the 10mm battery posts for a direct charge.
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E-Ray, 3LZ, ZER, LIFT
Joined: Sep 2007
Posts: 34,992
Likes: 12,385
From: NE South Carolina
Randall:
I have my C7 connected to a CTEK MUS4.3....8 step smartcharger. It is connected 100% of the time when not driving the C7. Even after driving the car, the CTEK takes a few hours (1-2) for the LED's on the CTEK MUS 4.3 to cycle through the charging process. These chargers deliver a very slow and low charge. There is never a fear of a quick overcharging when using these devices.
Other C7 owners might did disagree, but the with the mass amount of electronics in the cars they do drain the battery.
I have my C7 connected to a CTEK MUS4.3....8 step smartcharger. It is connected 100% of the time when not driving the C7. Even after driving the car, the CTEK takes a few hours (1-2) for the LED's on the CTEK MUS 4.3 to cycle through the charging process. These chargers deliver a very slow and low charge. There is never a fear of a quick overcharging when using these devices.
Other C7 owners might did disagree, but the with the mass amount of electronics in the cars they do drain the battery.
My car has always read a low voltage typically 12.4 to 12.45 volts. That is after it charges fully but after I wait 12 to 24 hours for the surface charge to dissipate. However it is my DD although I don't drive it every day. However after I used the CTEK charger and realized it was my battery not the charger or the car I have not used it again in 22 months.
Last summer I was gone for 18 days, no charger and the car started right up! When I do have any issues will replace the Delco with a AGM battery. There are some available now that fit.
Fully charged battery should be able to start the car after sitting for ~35+ days,
Last edited by JerryU; Aug 14, 2015 at 01:19 PM.
E-Ray, 3LZ, ZER, LIFT
Joined: Sep 2007
Posts: 34,992
Likes: 12,385
From: NE South Carolina
Team Owner
Joined: Mar 2012
Posts: 49,315
Likes: 3,919
From: Best Island in the U.S.
St. Jude Donor '12 thru '17
Burning Brakes
Joined: Oct 2014
Posts: 802
Likes: 122
From: Goodyear Arizona
Drove the car all last weekend and Monday. Connected the Deltran battery tender Monday afternoon and it showed steady red. Tuesday morning it was steady green. Won't be back for two weeks - no concerns.
Thread Starter
Le Mans Master
Joined: Sep 2012
Posts: 7,146
Likes: 1,940
From: Hagerstown MD
St. Jude Donor '15-'16,'18
I agree. I have 3 Battery Tenders and have used them for years on many different cars and my lawn tractor battery. Never had a problem. I was a bit surprised when I first connected it to my C7 after haven driven the car and got a steady red light which didn't turn steady green within an hour or so. It took several hours of charging to bring it to a steady green. Seems like this isn't unusual. All is well.
Safety Car
Joined: Oct 2014
Posts: 3,543
Likes: 854
Burning Brakes
Joined: Aug 2003
Posts: 1,070
Likes: 9
From: MARRIOTTSVILLE MD
Amazon.com.....just $1.37
Amazon.com: Battery Tender Deltran Cigarette Lighter Adapter 081-0069-5: Automotive
Amazon.com: Battery Tender Deltran Cigarette Lighter Adapter 081-0069-5: Automotive
Burning Brakes
Joined: Jul 2015
Posts: 920
Likes: 87
Randall:
I have my C7 connected to a CTEK MUS4.3....8 step smartcharger. It is connected 100% of the time when not driving the C7. Even after driving the car, the CTEK takes a few hours (1-2) for the LED's on the CTEK MUS 4.3 to cycle through the charging process. These chargers deliver a very slow and low charge. There is never a fear of a quick overcharging when using these devices.
Other C7 owners might did disagree, but the with the mass amount of electronics in the cars they do drain the battery.
Your charge is normal and most likely you will see a charged battery in the morning.
Instead of using the cigarette adapter in the hatch, I have my CTEK MUS 4.3 wired directly to the 10mm battery posts for a direct charge.
I have my C7 connected to a CTEK MUS4.3....8 step smartcharger. It is connected 100% of the time when not driving the C7. Even after driving the car, the CTEK takes a few hours (1-2) for the LED's on the CTEK MUS 4.3 to cycle through the charging process. These chargers deliver a very slow and low charge. There is never a fear of a quick overcharging when using these devices.
Other C7 owners might did disagree, but the with the mass amount of electronics in the cars they do drain the battery.
Your charge is normal and most likely you will see a charged battery in the morning.
Instead of using the cigarette adapter in the hatch, I have my CTEK MUS 4.3 wired directly to the 10mm battery posts for a direct charge.
Race Director
Joined: Jul 2010
Posts: 10,548
Likes: 176
From: Upstate NY
I don't normally bother with the tender during summer months but mine behaves the same as the OPs. It may show a little charge for a few hours, even after driving. But it keeps my battery healthy during down time and winter months.