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Battery woes

thumper

Active Member
Joined
Mar 6, 2012
Messages
28
Location
Ontario Canada
My XLR/V(s)
2008 XLR-V
I thought I’d share my latest adventures with 2008 XLR-V on the chance that what I have learned might help you with the care and feeding of your XLRs.

I live just outside Toronto, Canada so I don’t start the XLR much after top down weather. Maybe once a week or 2 weeks until mid November when I put it into storage for the winter.

About 3 weeks ago, I went to start it and the battery was very low. It did start but only just. After driving a couple of kms the DIC came on and said “Engine overheated, AC off” yet the temperature gauge was still at bottom reading indicating not even warm.
I drove another couple of kms and decided to pull over and check. The rad was cool and the hoses showed no sign of pressure in the cooling system so I continued on to see my mechanic friend. He checked the error codes and found faulted temperature sensor. He reset the code to see if it would come back and it did not. The DIC cleared and the temp gauge started reading correctly. Looks like the low battery caused an electrical aneurism in one of the computers.

On to the next problem:

Last week, I went to start the car and the AC Delco 85-6YR battery would still light up the dash but not crank the motor. I attached my battery tender (1.5a) and left it for a few days. (I had run a short pigtail from the battery up to the window so I could plug in with hood down.) I noticed that the yellow light on the tender would start flashing after an hour or so indicating that the battery needs to be checked. I checked the water level and it was down slightly but not down so far as to expose the plates. After a couple of days on the tender, I figured I would try to start again.

No way. Battery is completely dead! Of course the hood is latched, the doors and windows are closed and the trunk is locked. No problem, I said with a knowing smirk. I read the manual. All I have to do is insert the key that is hidden in my fob into the lock in the rear bumper and unlock and manually lift open the trunk giving me access to a manual door release. Once inside the car, I can release the hood and attach a real battery charger. Piece of cake.

There is an old Yiddish saying that comes to mind in situations like this: Man plans; God laughs. The key won’t turn. Now what?

I Figured I may as well try the key from my #2 fob and fortunately, it did work. I compared the two keys and they are quite different. I guess the previous owner got a replacement fob off eBay or somewhere and never go the key part changed. More about the key later.

Once I got the hood up, I connected up my 10A charger and away it went charging at 9A. After an hour it was down to 8A so it was looking hopeful. By next morning, it was down to 2A so I disconnected the charger and tried to start the car. It started fine but of course lost memory setting that had to be reset and windows indexed. I did notice that my Mild2Wild was set at Wild. I remember setting that the last time I used the car and I guess I had left it in the Wild setting. A quick search of the interwebs found that that could indeed explain the battery to drain. Good to know.

I also ran across another interesting theory about Keyless Entry systems. Normally when you turn off your car and walk away, after about 45 minutes, it goes into a deep sleep mode to minimize battery drain. Only the fob sensor and security systems are live. If you leave your fob within about 20 ft of the car, it never goes into deep sleep and that could drain the battery much quicker. Good to know. Also, in my case, every time I go out to the garage with the fob for my other car, a 2011 CTS Wagon, the XLR wakes up seeing a GM fob, says “that’s not me” and stays awake for another 45 minutes. I don’t know if this is the case but it could explain the XLR battery drain.

So, did the M2W drain my battery? Did the CTS fob cause the extra drain? Is the XLR battery now pooched from being drained right down?

Best check the battery first. Went to my mechanic friend and he did a load test and charger test and everything was ok but he said I should consider getting a new battery. Once they get drained right down, they are never the same again. (Unless you have a Deep Discharge Battery)
I decided to leave it for the winter (with the battery tender connected) and see what it’s like in the spring. When I do get a new battery, I think I’ll go for the Optima Yelowtop - Tractor Battery | Forklift Battery | YELLOWTOP® | OPTIMABATTERIES . It’s almost $300 with taxes and core charge but that or the Redtop seems to be the most popular replacement.

I drove the car around for a couple of hours to get the engine computer to relearn its stuff and took it in for the DriveClean Test so I don’t have to do it in January when my plate sticker needs to be renewed. It passed.

The car is now stored, covered and batter tender connected for the winter.

So I need a new key. I stopped at a GM dealer and expected that they would tell me I need to buy the entire fob at a price of somewhere around $1,000 but they said they could supply me with just the blank key for an extremely affordable price of $78.00. (plus tax plus cutting charge)

That’s $78.00 for this
$_12.JPG
!!!!!!!

Fortunately, eBay has a somewhat more affordable option at $5.25.
Uncut Smart Remote Replacement Key Fob Case Insert Blade for Cadillac Chevy | eBay
I ordered 3 to give out as stocking stuffers.
 

airmike

Seasoned Member
Joined
Feb 24, 2011
Messages
301
Location
parsons ks
My XLR/V(s)
2006 black raven xlr-v
Thanks for sharing. Good deal on the ebay key. Nothing like a "little" mark up to keep the dealers going. wow
 

xlrlist01

Seasoned Member
Joined
Oct 31, 2013
Messages
263
Location
HSV
I also ran across another interesting theory about Keyless Entry systems. Normally when you turn off your car and walk away, after about 45 minutes, it goes into a deep sleep mode to minimize battery drain. Only the fob sensor and security systems are live. If you leave your fob within about 20 ft of the car, it never goes into deep sleep and that could drain the battery much quicker. Good to know. Also, in my case, every time I go out to the garage with the fob for my other car, a 2011 CTS Wagon, the XLR wakes up seeing a GM fob, says “that’s not me” and stays awake for another 45 minutes. I don’t know if this is the case but it could explain the XLR battery drain.

Yeah, I have this one too. Manufacturers haven't thought hard enough about the fob going past the car for a few weeks if it just so happens that the car isn't being used. A battery tender is a necessary part of maintenance in all 'fob' cars it seems.

I second the advice to get a new battery. Once they have gone, that seems to be the end. If you have a battery that you can check the level in, it is the wrong technology and runs at the wrong voltage. The correct Delco battery runs at a slightly higher voltage than the traditional battery and your XLR is very sensitive to a poor battery. Old style battery technology will make the problems worse. The wrong technology battery might also hit fuel economy as the on-board electronics will suspect a battery defect and attempt to correct it by increasing the charging effort. This is expensive in gas.
 

Phrede

Seasoned Member
Joined
Jun 9, 2011
Messages
1,300
Location
xxxx
I thought I’d share my latest adventures with 2008 XLR-V on the chance that what I have learned might help you with the care and feeding of your XLRs.

I live just outside Toronto, Canada so I don’t start the XLR much after top down weather. Maybe once a week or 2 weeks until mid November when I put it into storage for the winter.

About 3 weeks ago, I went to start it and the battery was very low. It did start but only just. After driving a couple of kms the DIC came on and said “Engine overheated, AC off” yet the temperature gauge was still at bottom reading indicating not even warm.
I drove another couple of kms and decided to pull over and check. The rad was cool and the hoses showed no sign of pressure in the cooling system so I continued on to see my mechanic friend. He checked the error codes and found faulted temperature sensor. He reset the code to see if it would come back and it did not. The DIC cleared and the temp gauge started reading correctly. Looks like the low battery caused an electrical aneurism in one of the computers.

On to the next problem:

Last week, I went to start the car and the AC Delco 85-6YR battery would still light up the dash but not crank the motor. I attached my battery tender (1.5a) and left it for a few days. (I had run a short pigtail from the battery up to the window so I could plug in with hood down.) I noticed that the yellow light on the tender would start flashing after an hour or so indicating that the battery needs to be checked. I checked the water level and it was down slightly but not down so far as to expose the plates. After a couple of days on the tender, I figured I would try to start again.

No way. Battery is completely dead! Of course the hood is latched, the doors and windows are closed and the trunk is locked. No problem, I said with a knowing smirk. I read the manual. All I have to do is insert the key that is hidden in my fob into the lock in the rear bumper and unlock and manually lift open the trunk giving me access to a manual door release. Once inside the car, I can release the hood and attach a real battery charger. Piece of cake.

There is an old Yiddish saying that comes to mind in situations like this: Man plans; God laughs. The key won’t turn. Now what?

I Figured I may as well try the key from my #2 fob and fortunately, it did work. I compared the two keys and they are quite different. I guess the previous owner got a replacement fob off eBay or somewhere and never go the key part changed. More about the key later.

Once I got the hood up, I connected up my 10A charger and away it went charging at 9A. After an hour it was down to 8A so it was looking hopeful. By next morning, it was down to 2A so I disconnected the charger and tried to start the car. It started fine but of course lost memory setting that had to be reset and windows indexed. I did notice that my Mild2Wild was set at Wild. I remember setting that the last time I used the car and I guess I had left it in the Wild setting. A quick search of the interwebs found that that could indeed explain the battery to drain. Good to know.

I also ran across another interesting theory about Keyless Entry systems. Normally when you turn off your car and walk away, after about 45 minutes, it goes into a deep sleep mode to minimize battery drain. Only the fob sensor and security systems are live. If you leave your fob within about 20 ft of the car, it never goes into deep sleep and that could drain the battery much quicker. Good to know. Also, in my case, every time I go out to the garage with the fob for my other car, a 2011 CTS Wagon, the XLR wakes up seeing a GM fob, says “that’s not me” and stays awake for another 45 minutes. I don’t know if this is the case but it could explain the XLR battery drain.

So, did the M2W drain my battery? Did the CTS fob cause the extra drain? Is the XLR battery now pooched from being drained right down?

Best check the battery first. Went to my mechanic friend and he did a load test and charger test and everything was ok but he said I should consider getting a new battery. Once they get drained right down, they are never the same again. (Unless you have a Deep Discharge Battery)
I decided to leave it for the winter (with the battery tender connected) and see what it’s like in the spring. When I do get a new battery, I think I’ll go for the Optima Yelowtop - Tractor Battery | Forklift Battery | YELLOWTOP® | OPTIMABATTERIES . It’s almost $300 with taxes and core charge but that or the Redtop seems to be the most popular replacement.

I drove the car around for a couple of hours to get the engine computer to relearn its stuff and took it in for the DriveClean Test so I don’t have to do it in January when my plate sticker needs to be renewed. It passed.

The car is now stored, covered and batter tender connected for the winter.

So I need a new key. I stopped at a GM dealer and expected that they would tell me I need to buy the entire fob at a price of somewhere around $1,000 but they said they could supply me with just the blank key for an extremely affordable price of $78.00. (plus tax plus cutting charge)

That’s $78.00 for this
View attachment 4796
!!!!!!!

Fortunately, eBay has a somewhat more affordable option at $5.25.
Uncut Smart Remote Replacement Key Fob Case Insert Blade for Cadillac Chevy | eBay
I ordered 3 to give out as stocking stuffers.


I leave my Mild3Wild in the open position for extended periods with no issues. I doubt seriously that is your issue.

I do know that having a fob within 20 feet of the car will drain the battery PDQ. I have a yellow Optima and think it is the best fit for our cars, others may disagree. I never have a need to start the car when it is cold. Actually my car has only seen freezing temperatures at all since I bought it. I am pleased with the Optima.
 

klaptrapper

Guest
Joined
Sep 23, 2009
Messages
213
Location
Jacksonville, Florida
My XLR/V(s)
2006-V black, ebony
Battery

AHAAA!!! No wonder my battery was going dead in a few days. My fob hung on a hook in the kitchen, barely 10 feet from my car. I had to use a battery tender (and still will) to use my car without having to charge it's battery.
I'll keep it in the bedroom, for now on 35 feet from the car.

Rusty 06 V


I do know that having a fob within 20 feet of the car will drain the battery PDQ. - See more at: https://www.xlr-net.com/forums/cadillac-xlr-technical-discussion/8204-battery-woes.html#post58184
 

Phrede

Seasoned Member
Joined
Jun 9, 2011
Messages
1,300
Location
xxxx
It was an AHA moment for me as well when I discovered I could not leave the fob in my bedroom.


Another one of those little quirks that we need to learn as XLR owners. Maybe we should start a wiki/thread with things like this. Other things could be the indexing the windows and the infamous map lamp dash pushbutton.
 

05 GRAND DADDY

Seasoned Member
Joined
Jun 17, 2011
Messages
2,758
Location
South Central PA (Littlestown)
My XLR/V(s)
2005 Light Platinium Silver XLR
I thought I’d share my latest adventures with 2008 XLR-V on the chance that what I have learned might help you with the care and feeding of your XLRs.

I live just outside Toronto, Canada so I don’t start the XLR much after top down weather. Maybe once a week or 2 weeks until mid November when I put it into storage for the winter.

About 3 weeks ago, I went to start it and the battery was very low. It did start but only just. After driving a couple of kms the DIC came on and said “Engine overheated, AC off” yet the temperature gauge was still at bottom reading indicating not even warm.
I drove another couple of kms and decided to pull over and check. The rad was cool and the hoses showed no sign of pressure in the cooling system so I continued on to see my mechanic friend. He checked the error codes and found faulted temperature sensor. He reset the code to see if it would come back and it did not. The DIC cleared and the temp gauge started reading correctly. Looks like the low battery caused an electrical aneurism in one of the computers.

On to the next problem:

Last week, I went to start the car and the AC Delco 85-6YR battery would still light up the dash but not crank the motor. I attached my battery tender (1.5a) and left it for a few days. (I had run a short pigtail from the battery up to the window so I could plug in with hood down.) I noticed that the yellow light on the tender would start flashing after an hour or so indicating that the battery needs to be checked. I checked the water level and it was down slightly but not down so far as to expose the plates. After a couple of days on the tender, I figured I would try to start again.

No way. Battery is completely dead! Of course the hood is latched, the doors and windows are closed and the trunk is locked. No problem, I said with a knowing smirk. I read the manual. All I have to do is insert the key that is hidden in my fob into the lock in the rear bumper and unlock and manually lift open the trunk giving me access to a manual door release. Once inside the car, I can release the hood and attach a real battery charger. Piece of cake.

There is an old Yiddish saying that comes to mind in situations like this: Man plans; God laughs. The key won’t turn. Now what?

I Figured I may as well try the key from my #2 fob and fortunately, it did work. I compared the two keys and they are quite different. I guess the previous owner got a replacement fob off eBay or somewhere and never go the key part changed. More about the key later.

Once I got the hood up, I connected up my 10A charger and away it went charging at 9A. After an hour it was down to 8A so it was looking hopeful. By next morning, it was down to 2A so I disconnected the charger and tried to start the car. It started fine but of course lost memory setting that had to be reset and windows indexed. I did notice that my Mild2Wild was set at Wild. I remember setting that the last time I used the car and I guess I had left it in the Wild setting. A quick search of the interwebs found that that could indeed explain the battery to drain. Good to know.

I also ran across another interesting theory about Keyless Entry systems. Normally when you turn off your car and walk away, after about 45 minutes, it goes into a deep sleep mode to minimize battery drain. Only the fob sensor and security systems are live. If you leave your fob within about 20 ft of the car, it never goes into deep sleep and that could drain the battery much quicker. Good to know. Also, in my case, every time I go out to the garage with the fob for my other car, a 2011 CTS Wagon, the XLR wakes up seeing a GM fob, says “that’s not me” and stays awake for another 45 minutes. I don’t know if this is the case but it could explain the XLR battery drain.

So, did the M2W drain my battery? Did the CTS fob cause the extra drain? Is the XLR battery now pooched from being drained right down?

Best check the battery first. Went to my mechanic friend and he did a load test and charger test and everything was ok but he said I should consider getting a new battery. Once they get drained right down, they are never the same again. (Unless you have a Deep Discharge Battery)
I decided to leave it for the winter (with the battery tender connected) and see what it’s like in the spring. When I do get a new battery, I think I’ll go for the Optima Yelowtop - Tractor Battery | Forklift Battery | YELLOWTOP[emoji768] | OPTIMABATTERIES . It’s almost $300 with taxes and core charge but that or the Redtop seems to be the most popular replacement.

I drove the car around for a couple of hours to get the engine computer to relearn its stuff and took it in for the DriveClean Test so I don’t have to do it in January when my plate sticker needs to be renewed. It passed.

The car is now stored, covered and batter tender connected for the winter.

So I need a new key. I stopped at a GM dealer and expected that they would tell me I need to buy the entire fob at a price of somewhere around $1,000 but they said they could supply me with just the blank key for an extremely affordable price of $78.00. (plus tax plus cutting charge)

That’s $78.00 for this
View attachment 4796
!!!!!!!

Fortunately, eBay has a somewhat more affordable option at $5.25.
Uncut Smart Remote Replacement Key Fob Case Insert Blade for Cadillac Chevy | eBay
I ordered 3 to give out as stocking stuffers.

For those wondering about these FOBS to this key they will work with the 04/05 model XLR But only the lock /unlock and trunk buttons will work and you need to have it programmed and key cut at some locksmiths can or dealer! But mine works great no more carrying a FOB with the key hanging on it![emoji2]


Sent from my iPhone using Tapatalk
Dan & Wendy
"05 GRAND DADDY"
 

David_B

Seasoned Member
Joined
Aug 31, 2014
Messages
446
Location
SE Michigan
My XLR/V(s)
N/Z
AHAAA!!! No wonder my battery was going dead in a few days. My fob hung on a hook in the kitchen, barely 10 feet from my car. I had to use a battery tender (and still will) to use my car without having to charge it's battery.
I'll keep it in the bedroom, for now on 35 feet from the car.

Rusty 06 V


I do know that having a fob within 20 feet of the car will drain the battery PDQ. - See more at: https://www.xlr-net.com/forums/cadillac-xlr-technical-discussion/8204-battery-woes.html#post58184

Or stick your key fob in a metal box..
 

XLRATING

Seasoned Member
Joined
Jul 10, 2011
Messages
1,831
Location
Virginia
My XLR/V(s)
2006 Infrared XLR (Beauty); 2008 GT500 (Beast); 2007 Black XLR-V (Victor)
I leave my Mild3Wild in the open position for extended periods with no issues. I doubt seriously that is your issue.

I do know that having a fob within 20 feet of the car will drain the battery PDQ. I have a yellow Optima and think it is the best fit for our cars, others may disagree. I never have a need to start the car when it is cold. Actually my car has only seen freezing temperatures at all since I bought it. I am pleased with the Optima.

Interesting - I would have bet M2W was it as that is the only variable we have between the base (can sit a month with no tender, etc) & the V (won't start after less than 2 weeks). Both have the same battery, both fobs are far, far away. Time to give leaving M2W open a shot for a while.

The only other thought we've had for the V is the prior owner had a radar detector hard wired in & whether or not something is still draining juice for that (shouldn't be but we're considering everything)

Don't think it's a nearby CTS fob either - again, the XLR's are together & it's only the V with a problem.
 

Phrede

Seasoned Member
Joined
Jun 9, 2011
Messages
1,300
Location
xxxx
Interesting - I would have bet M2W was it as that is the only variable we have between the base (can sit a month with no tender, etc) & the V (won't start after less than 2 weeks). Both have the same battery, both fobs are far, far away. Time to give leaving M2W open a shot for a while.

The only other thought we've had for the V is the prior owner had a radar detector hard wired in & whether or not something is still draining juice for that (shouldn't be but we're considering everything)

Don't think it's a nearby CTS fob either - again, the XLR's are together & it's only the V with a problem.

I investigated the wiring diagrams and what you say makes sense.

I suppose the Mild2Wild could cause more drain since it is wired to a hot at all times line and it obviously uses some power to communicate with the fob. I don't think it would matter which mode it was left in since it interrupts the power to the control module. When the power is interrupted the exhaust is in the open mode. The other mode is stock operation. I'm curious enough to measure the drain difference with and without F29 inserted then I will know for sure how much the difference is.

I did have a problem like this with a previous bluetooth adapter.
 

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