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2009 XLR (Base) - Roof Top Motor FIX - Thermistor Issue

Jayharrington

Active Member
Joined
May 4, 2020
Messages
28
Location
New York
My XLR/V(s)
2009 XLR Platinum, Black on Black on Black
All -

So I was getting a message for about a week that said: Roof Top Over Temp. Long story short, as 05 Grand Daddy pointed out, I might have a thermistor issue. Turns out, that was the case - and I know what the source of the prombel was: I washed my car on an incline where my trunk end was lower than my front end - so, per gravity, the water naturally flowed to the back end. And, thanks to some compromised seals, this caused water to leak into the pump motor hold area, which ultimately put water into my pump.

So here's what I did: I ripped out the pump motor and used this video as a guide: YouTube.

During the removal process, noticeable amounts of water came out of the unit, particularly from some housing covers and a foam pad at the bottom of my pump. I tested the motor using a 12V battery - motor whirred like a charm. Tested wire connections, all checked out. Except for the thermistor.

The thermistor is located within the pump motor, but it is crimped shut with virtually no access. So, I used a hair dryer (on a low-heat setting) and dried out the thermistor for about 20 minutes. I plugged it back in, said a prayer, and voila! It worked. My roof top is now going up and down no issues. About a 3 hour job (with some dinking around in between).

I also noticed that water was congregating in the back right portion of the pump motor hold. My hole was in the front right portion; so I drilled a hole on the back right side, so water can more effectively drip out.

A couple of notes on prevention of getting water into your roof top motor:

-Inspect and Replace any seals on the trunk side (e.g. decklid seal, taillight seals) that could be a leak source. If not replacing, seal any holes with a sealing agent (I used silicone).
-If washing the car, cover the pump motor with something - plastic bag, etc. - and secure it - rubber band, plastic straps, etc.

I hope this helps the community!

Jay
 
Jay

Good find

This repair shop is a real expert….. a fine video in supporting the ''do it your self''

IAN:thumbsup
 
All -

So I was getting a message for about a week that said: Roof Top Over Temp. Long story short, as 05 Grand Daddy pointed out, I might have a thermistor issue. Turns out, that was the case - and I know what the source of the prombel was: I washed my car on an incline where my trunk end was lower than my front end - so, per gravity, the water naturally flowed to the back end. And, thanks to some compromised seals, this caused water to leak into the pump motor hold area, which ultimately put water into my pump.

So here's what I did: I ripped out the pump motor and used this video as a guide: YouTube.

During the removal process, noticeable amounts of water came out of the unit, particularly from some housing covers and a foam pad at the bottom of my pump. I tested the motor using a 12V battery - motor whirred like a charm. Tested wire connections, all checked out. Except for the thermistor.

The thermistor is located within the pump motor, but it is crimped shut with virtually no access. So, I used a hair dryer (on a low-heat setting) and dried out the thermistor for about 20 minutes. I plugged it back in, said a prayer, and voila! It worked. My roof top is now going up and down no issues. About a 3 hour job (with some dinking around in between).

I also noticed that water was congregating in the back right portion of the pump motor hold. My hole was in the front right portion; so I drilled a hole on the back right side, so water can more effectively drip out.

A couple of notes on prevention of getting water into your roof top motor:

-Inspect and Replace any seals on the trunk side (e.g. decklid seal, taillight seals) that could be a leak source. If not replacing, seal any holes with a sealing agent (I used silicone).
-If washing the car, cover the pump motor with something - plastic bag, etc. - and secure it - rubber band, plastic straps, etc.

I hope this helps the community!

Jay

Awesome that fixed it, but here’s better way to wash our XLR’s either waterless Spray on Wash N Wax or 1 Gallon of water in bucket an a capful solution with 2 microfiber towels and No Hoses needed! Roxy hasn’t been hose wash for about 3 years now! Oh and it Ships Free too!
Find them at Quality Products for Quality Cars – Powered by CroftgateUSA

Or use direct link to eBay
Bucket Style

Wash & Wax 8oz DIY Wipe on wipe off technology [1 Cap full in 1 gal of water] | eBay

Spray on Wash n Wax
AQUANIL-X 32oz. DIY Waterless Car Wash & Wax (Non Hazardous) | eBay


Sent from my iPhone using Tapatalk
 
Last edited:
The only way you get water IN your motor is if the drain hole for the cubby is plugged. I check mine every 6 months, the parts in that cubby are unobtanium for the most part.
 
Hey

About three weeks ago in a torrential rain storm, I noted a very small amount of water had gotten into my well. It got in there, as /i had driven through some standing water at hi way speed. Kind of sudden unavoidable and unexpected. i checked and found a very small insignificant amount of water in the well. Inspected the Top module and found it is only affixed by adhesive tape at the bottom . Why not, as I did, remove it and re-attach it to the side wall of the tub, similarly with double faced adhesive tape? Think that the potential for water damage has been greatly reduced . Also afixed a water shed "shingle" immediately above the unit, should any water come in from above. Wonder why this was not the original placement in the factory.

Bill
 
Bill S.

Very good, simple idea….. the water drain remains to be check ?.

There is room available in between the backrest of the seats, the consol space could be smaller and used for the top and suspension modules, the motor could have been installed in the trunk wheel housing area close to the VICM module, there seems to have dry room for them and access for the maintenance.

This fine car is build for the return of the owners to their dealership XLR maintenance and parts sales, even a bulb replacement is recommended in the owner manual by the dealer.

Since that venture with the corvette and its poor sales results with poor profits, this car builder let us down now with the no parts availability on many vital and captive items.

It is a shame…..

IAN:thumbsup
 
Bill S.

Very good, simple idea….. the water drain remains to be check ?.

There is room available in between the backrest of the seats, the consol space could be smaller and used for the top and suspension modules, the motor could have been installed in the trunk wheel housing area close to the VICM module, there seems to have dry room for them and access for the maintenance.

This fine car is build for the return of the owners to their dealership XLR maintenance and parts sales, even a bulb replacement is recommended in the owner manual by the dealer.

Since that venture with the corvette and its poor sales results with poor profits, this car builder let us down now with the no parts availability on many vital and captive items.

It is a shame…..

IAN:thumbsup

In regards to the light bulb I was going to go to my local auto parts store until my service guys said everything that needs to be done to change the bulb.


Sent from my iPhone using Tapatalk
 
All -

So I was getting a message for about a week that said: Roof Top Over Temp. Long story short, as 05 Grand Daddy pointed out, I might have a thermistor issue. Turns out, that was the case - and I know what the source of the prombel was: I washed my car on an incline where my trunk end was lower than my front end - so, per gravity, the water naturally flowed to the back end. And, thanks to some compromised seals, this caused water to leak into the pump motor hold area, which ultimately put water into my pump.

So here's what I did: I ripped out the pump motor and used this video as a guide: YouTube.

During the removal process, noticeable amounts of water came out of the unit, particularly from some housing covers and a foam pad at the bottom of my pump. I tested the motor using a 12V battery - motor whirred like a charm. Tested wire connections, all checked out. Except for the thermistor.

The thermistor is located within the pump motor, but it is crimped shut with virtually no access. So, I used a hair dryer (on a low-heat setting) and dried out the thermistor for about 20 minutes. I plugged it back in, said a prayer, and voila! It worked. My roof top is now going up and down no issues. About a 3 hour job (with some dinking around in between).

I also noticed that water was congregating in the back right portion of the pump motor hold. My hole was in the front right portion; so I drilled a hole on the back right side, so water can more effectively drip out.

A couple of notes on prevention of getting water into your roof top motor:

-Inspect and Replace any seals on the trunk side (e.g. decklid seal, taillight seals) that could be a leak source. If not replacing, seal any holes with a sealing agent (I used silicone).
-If washing the car, cover the pump motor with something - plastic bag, etc. - and secure it - rubber band, plastic straps, etc.

I hope this helps the community!

Jay

What did you do exactly to test the motor connections? I have a pump that isn't doing anything while in the car, but when i put 12v power to the motor, it spun like yours did.
 
Hi TXMX - hope you’re well! All I did was connect it to a battery source; which sounds like what you did. I also used a multimeter to check current flow in the thermistor wire to see if there was a short there. I found no current flow; which suggested the wire was bad. So the first thing I did (as opposed to replacing the wire connection) was dry the wire connection/thermistor out using a hair dryer. I let it blow on there for about 20 minutes on a low heat setting; then tested the wire connection again with a multimeter - and it was working now!

I hope this helps - good luck! If you have any more questions, feel free to ask!

Jay
God is Good!
 
Hi TXMX - hope you’re well! All I did was connect it to a battery source; which sounds like what you did. I also used a multimeter to check current flow in the thermistor wire to see if there was a short there. I found no current flow; which suggested the wire was bad. So the first thing I did (as opposed to replacing the wire connection) was dry the wire connection/thermistor out using a hair dryer. I let it blow on there for about 20 minutes on a low heat setting; then tested the wire connection again with a multimeter - and it was working now!

I hope this helps - good luck! If you have any more questions, feel free to ask!

Jay
God is Good!

Do you happen to remember which wire the thermistor is? On the tech 2 the temperature reading is normal, so I'm not sure if that means its good or not.
 
Had a very similar issue to yours just yesterday.

My Folding Top sequence had always been to let go of the button on the last step, and then hold it again for the sequence to complete. The last step where the full trunk lid goes down, and in reverse when the lid is going up.
I figured one of the sensors (potentiometers) is out of spec and thus why I need to let go, then hold the button again for the sequence to come to an end.

Not yesterday. While I was holding the button through the sequence as usual, the top stopped where it usually does - but I didn't take my finger off the button - I kept holding the button for about 15 seconds, when it didn't go anywhere, I let go of the button then press it again and the sequence went just fine.

I go on my marry ride, reach the destination and put the top up, (not holding on the button this time) all goes fine.
Problem starts when I get back into the car 20 minutes later, I smell a strong burning odor of plastic coming from the trunk are where the hydraulic pump and control modules are. After a quick visual inspection, I see no leakage or damaged wires/connectors. Get in the car, try to operate the FT and I get an error on the dash "Top too cold to move". I hope for the best and wish a morning start would be back to normal. Not the case.

I read up on your thread, which was a great find! I also sent "Top Hydraulics" a message, and hope to hear back from them soon. I wonder if my problem is indeed the thermistor of the pump, and that I actually have the reverse of your problem. My pump probably got too hot in those 15 seconds I kept my finger on the button, and fried the thermistor. This is just my assumption. I want to take it apart today and see if I can find out more about the issue.
 

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