Convertible top troubleshooting

I am working my way round the car problem by problem and after tidying up the engine bay and dealing with suspension, I started work of the convertible top, which until today, did nothing when the center console switch was pressed, no top movement and no windows movement down. Checked that handbrake is on, car is in park and ignition was in 2nd position. So here is what I have done so far:

Removed all 3 electric window/top switches and electrically tested, which all acted the same on continuity test (assuming they are all the same)
Disconnected the plug to hydraulic motor and when I pressed the the top-down switch this time, the rear quarter windows went down.
Checked the hydraulic fluid reservoir behind the pump and the level was very low, so I refilled with hydraulic fluid and when I pressed the top down switch this time, the top came down, but wouldn’t go back up again.
Had to top up the reservoir several times to the max line, so seems there has either been a leak, or it has just never been maintained for years.
I moved 3 of the relays around in the back to make sure that the to-up relay wasn’t bad, but same result.
I manually raided the top twice (ensuring the switch on the pump was set to manual each time) to cycle the system, but have the same issue each time…the top won’t go back up.

Any ideas what would stop the motor/pump reversing the hydraulic flow if the relays are all good? Could it just be needing bled, which the manufacturer manual tells you to remove the pump and rams to do…which I really don’t want to have to do.

Problem solved. Didn’t know if I should delete post, or leave up in case someone else has the same issue in the future, so decided to leave up.

Turns out I did have an intermittent issue with the roof switch in the center console. I figured this out by plugging the roof connector into one of the window switches and it worked both up and down. Tore the roof switch down to the component level, cleaned with contact cleaner, polished and rebuilt. Works like new! So ultimately the issues here were dirty switch AND low fluid level in the hydraulic pump. Now that I know all is good with the mechanism, I can go ahead with ordering the new top and keep moving forward.

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I had a similar issue with my '89. I didn’t have the low fluid problem, but I did have the switch problem…when pressed it would go down, but not up. Replaced the switch and all was good.

Glad you were able to solve your issue.


Turns out I also had an issue with the hydraulic pump motor shaft seal. $15 on ebay and probably an hour to tear down, problem solved. Now I understand why the fluid level was low, since fluid was going from reservoir, past the shaft and through the motor.

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