Folding Top Problem - B3670

[knight rider]

I have spent considerable time reading recommendations on the site and greatly appreciate all of the input that is available. I'm hoping to obtain some verification from the community on what is needed to resolve my problem.

The other day after lowering the top for the first time this season there were no problems in lowering but when I tried to put the top up I received the "TOP MOTOR OVERTEMP" message and the process terminated. When I took it into the local dealer they provided me with the analysis listed below along with an estimate of $4656 for repairs. My concern, aside from the price, is that if the top down button is pushed shouldn't the first two steps in the sequence take place before it fails even if the hydraulic pump has failed? Additionally, doesn't it seem unlikely that the tonneau sensor, liftgate lock and the pump would fail simultaneously? Admittedly, I am not the most technical person but I want to at least understand my options before considering a costly repair like this.

Repair Analysis:

- Rear Tonneau position sensor times two needed
- Pump motor assembly and oil needed
- Lift gate lock needed
- B3669 Folding rear tap signal open
- B1297 trunk unlatched. Signal current lid pull down
- B3670 pump motor temp sensor circuit checked and performed TAP, check for codes B3669-folding tap rear deck lid, and rear tanneau posture, open.
- B1297 - trunk unlatched signal. circuit lid pull down
- B3670 - pump motor temp sensor circuit fault, tested, from module, para out when command on 2 of poss module also.

 

[ccclarke]

Which two "first steps" are you referring to that aren't happening? Once the Folding Top Control module gets the OVERTEMP warning, it shuts everything down. As Pvt Hudson yells in "Aliens", "Game Over, Man!"

As for the motor overtemp; Being sealed, you don't have much of a choice but to have the motor replaced/refurbished for $400 by a vendor in Oregon who's been recommended on this site.

Depending on how handy you are, you can remove the motor yourself, but make sure you catch the oil as the lines are disconnected from the manifold.

Each hydraulic line is labeled and there's a corresponding mark on the manifold to aid in getting them on the right fitting, so the first time you test it, the roof doesn't do a James Bond ejecto-routine.

Be aware you'll need a new set of O-rings when re-installing the hydraulic lines to the manifold. While you're at it, I'd spring for the heavy-duty hydraulic lines offered by the same vendor. You'll still be money ahead over what a dealer would charge. It wouldn't hurt to have some extra oil available if the reservoir goes low as the empty lines fill.

After the pump is replaced, then you can accurately determine what else may be wrong with the system. I doubt that many components failed simultaneously if it was worked before, unless your car suffered a lightning strike or the rear compartment flooded.

CC

 

[knight rider]

Thanks CC! I should have clarified about the "first two steps" being 1. Windows lowering & 2. Rear deck lid unlatches. I also was not aware that the motor overtemp warning was a clear indication that the pump had completely failed.

Since the B3670 code indicates that the pump is shot, does that also mean that the B1297 & B3669 code are indicating that the liftgate lock and tonneau position sensor need replacing as well?

 

[ccclarke]

The OVERTEMP message is an indication the thermistor has determined the motor is running too hot. While the motor could be bad, the thermistor could also be the culprit. Being a closed unit, a cheap component can seal the doom of the entire assembly. It isn't like the motor runs very much. . .

I've got an old hydraulic pump from my first failure -the day after I bought my XLR. (The 666 ID on the VIN should have been my first warning. . . ) Anyway, the thermistor is visible at the rear of the housing behind the motor windings and it might be possible to cut the leads and extract it, leading to a way to install a new component. Maybe one of these days I'll take a crack at it with my most technical mentor, Mr. Six-pack.

CCC

 

[knight rider]

A big thank you to CCC and everyone else for your help. I have taken the XLR into a local convertible repair shop called Riggs Bros. for the pump replacement as the cost was half of what the Caddy dealer wanted. Will report back next week on how things turn out.

 

[ccclarke]

Glad it worked out for you.

Here's a cheaper source for GM's expensive hydraulic parts and most are upgraded parts: Cadillac Convertible Top Hydraulic Cylinder Rebuild/Upgade Service - Top Hydraulics, Inc

CC

 

[pure zen]

Look at the VIN# before buying,,,,,

CC Quote: "I've got an old hydraulic pump from my first failure - the day after I bought my XLR.

(The 666 ID on the VIN should have been my first warning. . . )"




CC,,, You are one of the reasons I return to the site nearly everyday,,,,just to read your knowledge of the XLR, but now you ad humor....
Awesome!!!

 

[knight rider]

Ended up getting the hydraulic pump replaced by a local shop in the Chicago area called "Riggs Brothers" for a total of around $2,400. Works like new and cost about $2,000 less than what was quoted by the local Cadillac dealer.

Thanks to everyone for the help.