My wife's '97 XK-8's top was being raised, got hooked by the latch but then stopped before being snugged down to the windshield frame. The back windows didn't close and "HOOD LATCH FAIL" came up on the dash. The top wouldn't go up or down and no sound came from the pump. I suspected a latch lube deficiency followed by a logic breakdown in the control module.

I've tried to read through most of the posts on convertible problems. I was able to fully close the roof with the Allen wrench. I then disconnected the battery for ten minutes, touched plus-to-minus terminals and reconnected but the error message remains and the top switch is still totally unresponsive. The fluid in the pump reservoir is at the half-full level.

I've downloaded the 10-page TSB but there doesn't appear to be an obvious trouble-shooting approach for my symptoms. I'm nervous about manually moving the top up and down, perhaps doing even more harm than good based on the cautions in some of the posts.

I ran across the following on a roadfly.com forum in response to an owner reporting the same problems as mine:

"I would disagree with it being electronics. I had the same thing happen to my car. What happens is that the latch does not open completely before the top starts pressing on it. When that happens is does just what Kathryn describes, absolutely nothing. To resolve it enough to drive all you need to do is open the line on the pump and use the allen wrench (fastened next to the pump) to manually open the latch. The stem of the problem is as Kathryn said, that the fluid solidifies in the latch mechanism, and needs flushed with the newer fluid. Rather than take my car to Monte Shelton (also my local dealer) who quoted me $400 over the phone, I did it my self for a cost of $15 for the fluid (Monte Shelton wanted $47 for the same container of fluid). "

Is the problem hydraulic or electrical? And can anyone suggest a next step for me to take?

Bob

 

My suggestion would be to first flush/fill with new fluid (Pentosin, as I recall) and while you've got it open check and clean the various electrical connections you'll find.

I would strongly consider installing the Pressure Reduction Valve you'll find mentioned here on the forum. $280 well spent in my opinion and an easy DIY install. Your car is of the age and components that most benefit from the upgrade.

 

You must get the top closed before the windows will close. I would first check the level of the fluid and check that the petcock on the pump is closed. Latch the roof manually with the allen wrench, then push the CLOSE button this will apply pressure to the rams and then the windows will close. This system is electrical and hydraulic and all must be in sequence. If the hyd fluid is green is might have been replaced. Your system may be low on fluid that is often caused by leak ear the header or at one of the rams. You can go to my page and read a host of information on the roof operation.

 

Spurlee, I assume I can find some instructions that will show me how to change the fluid here on this forum so I'll search for those. It was flushed in 2001 but after nine years, it probably makes sense to replace the fluid and I'm assuming that that would be a good time to add the pressure reduction valve, too.

Gus, as I mentioned in my OP, I've already been able to get the top latched using the Allen wrench but neither the top switch nor the door switch cause the windows to raise nor the pump to operate, which sounds like something electrical. The car has 73K miles but at 47K miles (11/01), the dealer "performed top system flush" and charged me for a seal, hydraulic fluid and a "pyroil brk clean" in response to the top occasionally not going back up. The hydraulic fluid is clear, not green, so I assume from your post that that means it's old. But the fluid level appears to be at the half-way mark on the reservoir. Is that the full line?

I've looked at the various pictures and posts related to convertible tops and haven't seen evidence of leaks in the header, the rams or the pump. All fuses are OK and there's no evidence of shorts/damage in the relays if, in fact, such damage would be visible.

After changing the fluid, if the top switch still is unresponsive, should I try moving the top up and down manually (after setting the pump valve to manual and pushing on the rams)?

Bob

 

Bob,

I suggested for you to latch the roof manually because of the micro switches in the system will not let you go the next level until they are satisfied . See chart http://www.gusglikas.com/AutoRepairHydHose.htm You will also see an update for 7/17/10 with a tsb 501-11 and it will explain all the switches and positions involved. Now people have suggested to open then close the roof manually. I see that as a placebo! If the switches are not satisfied it will not go to the next level. You say the pump is not working, this could be caused by a fuse or a relay in the trunk that is blown or failed or that the micro switches will not let it go to the next level. http://www.gusglikas.com/AutoRepairH...lOperation.htm Start from scratch and check the fluid level, petcock and the fuse and relay. I spent two years with this system and have nearly all the info you need on the roof on my page. Changing the fluid should be the last thing you need to do right now.

 

I've checked the fuses but will check some of the other things you mentioned. As stated earlier, the latch has been closed and the top secured using the Allen wrench but the windows are still down and will not close when pressing the top-up switch. Trying to put the top down doesn't work, either. I've been assuming that the pump isn't working because I hear no sound when I press on the top button (up or down). Could it be that the pump's working but nothing is moving, e.g., due to a leak or such? But if that were the case, there wouldn't be any more fluid in the pump's reservoir, right?

Bob

 

Have you attempted to close the roof with the key in the door? If not try that next, if that fails then - If the pump is not working then lift the right rear lift to the locked position. You may need a 2x4 about 3ft ling to do this. Look behind the curtain on the right, you will see the roof linkage where the ram is attached, take and lift the linkage until you feel it lock into place. If you use the 2x4 do not force or bend the linkage. Once that is closed your windows will close when you press the roof close button.

Check your PM

 

Gus, sorry for the delinquent response...company from out of town. First, the top (and pump) don't respond to either the top button or using the key in the door. So I tried using a board to lever up the right arm under the back window. But it appears that the arm is already as high as it wants to go (i.e., the top seems to be fully up). I'm afraid to put too much pressure on that arm for fear of damaging it. The arm coming up from below has two arms attached to it about 1 1/2" apart. Where those two arms reach the headliner, they're still about 1 1/2" apart...should they converge to be almost touching when the top is fully up? If not, perhaps the top is already fully up yet the windows will still not rise.

I have continuity-tested all of the fuses that are associated with the top's operation and a visual inspection of the relays doesn't show anything suspicious. The fluid reservoir has fluid just above the center-line of the reservoir (and contrary to what I said in an earlier post, it appears that it's green, not colorless).

Hoping you can help me with the next step...

Bob

 

Check your PM!! "Private Message"

 

My message to you was to call me.
The pump will not work without power (fuses, relay and check plugs to pump) and satisfied switches in the header and the ram.
If the roof latch at the header is not completely closed/latched with the allen wrench the pump will not run to apply pressure to the rams.
If the ram on the right has not extended all the way the switch in the ram will not allow the windows to go up. Check the wire at the ram on top.
And that is where we are!
Now the pump could be bad but I find it hard to believe because I have not seen one that failed on the forum. So I would be looking at fuses, swap the relays, check connections at the pump, open and close the header latch pulling the roof closed and apply pressure to the right side ram. Using the 2x4 was to apply pressure to lift the ram behind the window not the window.

 

The number i have does not work. Wrong number!