How to get into your XLR with a dead battery and no emergency key

[Hawk58]

I recently found myself in an untenable situation. I was out of state with my 2006 XLR on business and the weather turned cold overnight from 50 degrees the day before to 25 degrees the next day. I went out to the car to run an errand and could not open the door. To my supprise the battery was dead, nothing from the key fob, nada. My mind raced as to what to do next. Here I am, dead battery, late on saturday afternoon, emergency key on the other key fob at home in another state and no GM dealer nearby. At a loss as to how the battery was dead with no previous symtoms I went back inside. Turned on my laptop and headed to the XLR net and XLR forum to try to find a solution. The only answer I found was to go to the dealer with the VIN to have an emergency key cut on Monday. Not satisfied I headed to the corvette forum to search for a solution. In the C6 section I found a post by Cincykid who had a similar situation in his C6 with a quick solution. He found the cooling fan control module on the back of the radiator at bottom, pulled the weatherpack connector, and hooked his battery charger to the Battery side of the connector and within a few minutes was able to power-up the car to open the door, pop the hood release and then jump the battery to get his C6 going. Now to all the skeptics telling me I will fry the electrical system, hang in there with me. After reading Cincykid's post and comments by C6 forum members chastising him for not hooking his battery charger to the positive terminal on the starter motor to accomplish the car entry to avoid any damage to car relays, modules or circuitry, I was not convinced I wanted to take the risk and started to make plans for visiting the dealer on Monday. Having a copy of the 2005 XLR GM service manual on my laptop I researched the wiring diagrams for the engine cooling system. While there is an early and a late design listed, my manual was missing the schematic for the late design, damit, now what? When looking at the schematics, I noted that the cooling fan circuit is fused at the underhood fuse block. I also noted that some circuit diodes were listed in the underhood fuse block. Not convinced that I could power the car battery (door circuits) safely via the cooling fan circuit, I decided to sleep on it before I made a move. The following day, I did some more schematic research and determined that the only way to get power to the battery of a locked XLR is via the cooling fan circuit and the battery cable at the alternator. Since getting to the alternator is not possible without jacking up the car, I opted for hooking a battery charger set to low amps (10 amps or less) to the cooling fan circuit and within a few minutes there was power to open the door and pop the hood, mission accomplished. Do not apply full battery power via jumper cables to this circuit as high amperage applied could cause circuit damage. I have driven the car since with no adverse affects. This procedure worked for me, but use at your own risk, consider this a pure emergency access procedure. I bear no responsibility for damage that could occur to your car using this procedure. Enclosed is a photo take from Cincykid's post with his battery charger hooked up to his corvette.

 

[Stella]

Good job that's using your head. I like it. I put a magnet box under car with emergency key.

 

[Hawk58]

Stella,

Thanks, I wish I could take credit for the procedure, but the corvette guys came up with the idea. Since we have the same base platform it works on the XLR. BLUF, never go anywhere without the emergency key! I still don't know the real reason the battery was completely dead??

 

[mtrocket]

Good job that's using your head. I like it. I put a magnet box under car with emergency key.

Where did you put your magnet box??

 

[Stella]

If not mistaken there was metal behind the bumper area. Where the muffler brackets fasten to the frame. To help me sleep I put a zip tie through two holes in frame around box as backup. Cars in storage or else I would get you a picture

 

[mtrocket]

If not mistaken there was metal behind the bumper area. Where the muffler brackets fasten to the frame. To help me sleep I put a zip tie through two holes in frame around box as backup. Cars in storage or else I would get you a picture

That's a good idea... mine is also in storage. When I get it out, I'll take a look and see where I can put one.

 

[05 GRAND DADDY]

Just to mention to all that the key to open the the trunk is just a regular key you can have made anywhere there is no computer chip or anything like that in this key. Just make sure you check the key to see that it is cut correctly so that it works before hiding it !


Sent from my iPhone using Tapatalk Thanks Dan

 

[Phrede]

I did something similar thru the hydraulic pump connections in the trunk with a current limiting power supply. My problem was that the emergency door release was not as described in the manual. It seems the location changed in the later years, but not the manual. A tech from the dealership came and could not find it either. He left with no suggestions. A good thing it happened in my driveway.

I'm a little confused here though. Is not the trunk release key stored in the fob? Why/how could you not have it with you?

I strongly recommend everyone do this before you HAVE to just so you know where everything is and how it works.

 

[BusaMan]

I did something similar thru the hydraulic pump connections in the trunk with a current limiting power supply. My problem was that the emergency door release was not as described in the manual. It seems the location changed in the later years, but not the manual. A tech from the dealership came and could not find it either. He left with no suggestions. A good thing it happened in my driveway.

I'm a little confused here though. Is not the trunk release key stored in the fob? Why/how could you not have it with you?

I strongly recommend everyone do this before you HAVE to just so you know where everything is and how it works.

Good advice, Phrede. On my '06, we have a different fob, and the key is a separate, regular key, attached to the fob by a ring. On the later models, they incorporated the key into the fob [better idea, IMHO].

Tim

 

[05 GRAND DADDY]

I have always wondered why no aftermarket company have not designed like a leather pouch that holds FOB & KEY


Sent from my iPhone using Tapatalk Thanks Dan

 

[Stella]

Just a question is the emergency keyswitch mechanical or electronic.

 

[First Robin]

Just a question is the emergency keyswitch mechanical or electronic.

If it was electronic it wouldn't do you any good if your battery is dead. You insert key, while turning it you use the other hand to manually lift up the trunk lid. Hope that helps.

 

[Stella]

Guess I should think before I write

 

[First Robin]

Guess I should think before I write

I think the bad Chicago air probably has something to do with it.

 

[Victor-V]

Just a question is the emergency keyswitch mechanical or electronic.

If it was electronic it wouldn't do you any good if your battery is dead. You insert key, while turning it you use the other hand to manually lift up the trunk lid. Hope that helps.

The key does operate a mechanical lock and the trunk hydraulics (if there is enough battery power for the hydraulics to work). If the battery is weak or dead, the key unlocks the trunk lock and you have to lift it by hand. You need to be careful when you do this because you can get the trunk higher on one side than the other as you are lifting. I don't know if that hurts the hinges but it seems like something you want to avoid.

I had this happen to me about a month ago because my battery was weak and the FOB would not unlock the doors.

 

[cubby558]

Victor-V is correct, if there is enough battery power, turning the key will also run the hydralics and lift the trunk. There are some electronics to the trunk latch, which I found out last year on the PA trip. I could not open my trunk with the fob, trunk button, dash button or operating the top. The latch was not releasing, but the hydralics were trying to open it. The trunk release key was the only way I could gain access. A new trunk latch mechanism was installed under my CPO warranty when I got home. You don't want to have to pay this expense, if you can help it--I was quoted over $ 800.00!! It is not that hard to change out either. Didn't understand the high cost.

Phrede,

The '08-'09 models were the only ones to have the fob with the internal key. All the previous models had a key and fob seperate. I've converted mine to the newer fob, as it seems a little more slender and easier to carry in my pocket.

 

[Phrede]

I didn't realize that the pre'08 fobs had the emergency key separate. That does seem like a recipe for disaster.

I suggest if your are doing a drill to not use the hydraulics to open the trunk and do it manually. The feel and apparent weight will surprise you. Just be sure to keep it straight when lifting.

 

[Victor-V]

I didn't realize that the pre'08 fobs had the emergency key separate. That does seem like a recipe for disaster.

I suggest if your are doing a drill to not use the hydraulics to open the trunk and do it manually. The feel and apparent weight will surprise you. Just be sure to keep it straight when lifting.

The only way to test it without the hydraulics is to disconnect the battery (as far as I know).

 

[Phrede]

The only way to test it without the hydraulics is to disconnect the battery (as far as I know).

Does the trunk continue to open after the key has been release/removed? If so, I expect you are right.

 

[Victor-V]

Does the trunk continue to open after the key has been release/removed? If so, I expect you are right.

I believe so. I will check when I get home later.