Help! 2005 XLR Dead Battery Multiple Problems

[JimJ]

More Problems!!! Now the top won't raise!!!

I took the XLR out for a test drive. Everything seemed to work well. When I got home, I put the top down. It worked just fine. NOW THE TOP WILL NOT GO UP!!! When I try to have the top go up, the tonneau cover opens, then "nothing"!!!

The top worked perfectly before I had to change the battery. I had the car serviced last year, and the top was fully checked out and no problems were found.

The car is always garaged and has never been out in the rain since I've owned it. I changed the battery before, about 3 years ago, and had none of these

There are no DIC Messages about trunk obstructions. The trunk is fully latched, and opens up perfectly when using a key FOB or the lever in the passenger compartment. Also, I thought I fully "re-indexed" the windows before I tried to lower and raise the top.

I'm at a loss other than taking it into my closest Cadillac dealer, about 20 miles away from my house.

Sorry to keep pestering everyone. I thought changing the battery would be simple, as I'd done it before.

Thanks again--Jim

 

[JimJ]

Top Now Working!!!

I took the XLR out for a test drive. Everything seemed to work well. When I got home, I put the top down. It worked just fine. NOW THE TOP WILL NOT GO UP!!! When I try to have the top go up, the tonneau cover opens, then "nothing"!!!

The top worked perfectly before I had to change the battery. I had the car serviced last year, and the top was fully checked out and no problems were found.

The car is always garaged and has never been out in the rain since I've owned it. I changed the battery before, about 3 years ago, and had none of these

There are no DIC Messages about trunk obstructions. The trunk is fully latched, and opens up perfectly when using a key FOB or the lever in the passenger compartment. Also, I thought I fully "re-indexed" the windows before I tried to lower and raise the top.

I'm at a loss other than taking it into my closest Cadillac dealer, about 20 miles away from my house.

Sorry to keep pestering everyone. I thought changing the battery would be simple, as I'd done it before.

Thanks again--Jim

Being IMPATIENT, I "re-ndexed" the windows again. I then backed the XLR out of the garage, so if the top came up, it wouldn't hit the garage door opener. I then folded down the sun visors just taking a wild guess, before I tried to get the top to close. "LO AND BEHOLD!!", everything works great. I opened and closed the top 3 times, and everything is ok. GO FIGURE!!!

Jim

 

[Tinker]

Hi Jim,

Sounds as if:
1. The top control module isn't opening the solenoid valves that operate the top's hydraulic cylinders or,
2. One, or more of the Top's hydraulic cylinders has deteriorated seals (the seals degrade over time, whether the top is operated frequently, or not) or,
3. the trunk shelf (Cargo Cover, page 2-43 of the Owner's Manual) isn't fully seated, or its position sensor has failed.

Any of the three will produce the same symptoms you describe. The easiest to check is the Cargo Cover position, and next will be listening for the snap of the micro-switch when it is fully seated (Micro-switches seldom fail, and I have yet to find a bad one which was able to "snap" when actuated).

Top Hydraulics Inc. in Florence, Oregon will rebuild cylinders for about $100 each, or $700 for the full set of eight. Check out their website

A Tech 2 Scan tool is required to work on the Top Control module, and the solenoid valves are part of the hydraulic pump assembly which costs $400 to repair at Top Hydraulics.

Hope this helps

 

[ccclarke]

Glad to hear your folding top is working as it should.

If the luggage barrier is not in place, or the microswitch is stuck open, the DIC will display an error message when the Folding Top Control switch is pressed, so if you didn't get that, you can rule that out.

If the Front Tonneau raises and the Rear Decklid doesn't, the former's position sensor value is probably not matching what is stored in the Folding Top Control module. This is fairly common, especially if the sensors have been idle for long periods of time (like Winter storage.).

In the next few weeks, there will be a higher-than-average number of top problems posted here. This is to be expectd as XLRs come out of hibernation. Cycling the folding top can fix some sensor-related problems, while re-learns with a Tech 2 cure a lot of the others. The rest of them need replacement when all else fails.

The solenoid valves in the hydraulic manifold are nearly bullet-proof. The hydraulic pump (especially the thermistor that controls it) is less reliable than the pump itself.

Broken hydraulic lines (especially those that live within the top are susceptible to splitting as they age. This can be a nightmare if it happens under the headliner.

In in summary, from most to least prevalent folding top failure causes:

Position sensors
Folding Top Control modules (from flooded trunk compartments)
Pumps (taken out when submerged)
Pumps (bad thermistors)
Position switches
Hydraulic Cylinders
Hydraulic lines
Rear pull-down cinch (These have cheap plastic innards)

The majority of folding top failures are position sensor-related. 2004-2005 (by virtue of their age and quantity produced) models seem to be affected the most.

CC

 

[Tinker]

Thanks CC, I learn something new every day. Could you tell me why there are so many sensor problems? Do they need to be upgraded to a higher quality part, or is something else causing the problem?

 

[ccclarke]

I've posted a lot regarding position sensors over the years, and at the risk of repeating myself, basically, the position sensors have a (plastic) pin and fastener mounting scheme. Over time, the fastener can loosen allowing the sensor to totate slightly, throwing off the resistance value. The sensors are potentiometers which out pit an analog voltage interpreted as "counts" by the FTC module. It doesn't take much of a count change to throw the system out of whack either. Over the years, the calibration table parameters in the FTC module have been loosened up with software updates, but the real problem is the methodology of the sensors themselves. Digital encoders would have increased the reliability quite a bit. After replacing a position sensor, they should be bonded in place, since a single fastener isn't sufficient over time to keep them solidly positioned.

If a re-learn becomes a temporary fix, it means the sensor is either shifting in position while operating or the pot is going bad and should be replaced.

CC