Intermittent Top Movement - 99 986 Base

[Artee]

Hey, I have been reading on this forum all day trying to figure out how I can diagnose this problem, and I have done most of the basic checks, but first, I'll give some background of my history with this car. My previous car was an Acura RSX-S, and it was rear-ended and totaled. I looked at a few cars, but narrowed my search down to a Z4 3.0. My friend, who owns a Cayman, suggested that an early Boxster was in my price range, and I found one almost immediately, with 15,201 miles, about two hours away from where I lived. I had test driven the Z4, and when I drove the '99 Boxster 2.5, it was a done deal. A few days later and I took the car home. While I was at the owners house, I tested the top functionality to make sure it was 100%. About two weeks later, I started having infrequent, but strange top problems.

Everything seems alright, Parking brake lights up, windows go down, but the top doesn't move. I have noticed that it seems to get stuck down almost exclusively, until today. Yesterday was a decent day out, so I put the top down. When I got to my destination, it wouldn't go up. In the past, I had assumed this was simply an error of the top thinking the parking brake wasn't on, the door was open, etc. In the past, it has also worked again after a few feet of driving. Yesterday it was down and would not electronically go up until today about 29 hours after I put it down. I tried to move it down slightly, just to see if it was working fine again, with the intent to put it back up immediately, so that it wouldn't get stuck all the way again. Now it won't go down. Luckily it is not stuck down, we are supposed to get rain tomorrow. So, I'm guessing it's either a Fuse, Relay, the Dash Switch, or a Faulty connection/wire somewhere. Let me know if you guys have any other suggestions for things I might check. By the way, the top motor doesn't make any noise whatsoever, so I think it's likely electrical and not mechanical. Thanks in advance for any help.

[1schoir]

Hey, I have been reading on this forum all day trying to figure out how I can diagnose this problem, and I have done most of the basic checks, but first, I'll give some background of my history with this car. My previous car was an Acura RSX-S, and it was rear-ended and totaled. I looked at a few cars, but narrowed my search down to a Z4 3.0. My friend, who owns a Cayman, suggested that an early Boxster was in my price range, and I found one almost immediately, with 15,201 miles, about two hours away from where I lived. I had test driven the Z4, and when I drove the '99 Boxster 2.5, it was a done deal. A few days later and I took the car home. While I was at the owners house, I tested the top functionality to make sure it was 100%. About two weeks later, I started having infrequent, but strange top problems.

Everything seems alright, Parking brake lights up, windows go down, but the top doesn't move. I have noticed that it seems to get stuck down almost exclusively, until today. Yesterday was a decent day out, so I put the top down. When I got to my destination, it wouldn't go up. In the past, I had assumed this was simply an error of the top thinking the parking brake wasn't on, the door was open, etc. In the past, it has also worked again after a few feet of driving. Yesterday it was down and would not electronically go up until today about 29 hours after I put it down. I tried to move it down slightly, just to see if it was working fine again, with the intent to put it back up immediately, so that it wouldn't get stuck all the way again. Now it won't go down. Luckily it is not stuck down, we are supposed to get rain tomorrow. So, I'm guessing it's either a Fuse, Relay, the Dash Switch, or a Faulty connection/wire somewhere. Let me know if you guys have any other suggestions for things I might check. By the way, the top motor doesn't make any noise whatsoever, so I think it's likely electrical and not mechanical. Thanks in advance for any help.

Artee:

Congrats on your new ride! Drive it in good health!

Assuming that your parking brake idiot light is on (when you pull up on the parking brake) and that your windows drop down the 4 inches when you pull down the convertible top latch to unlock it, then your most likely suspect is one of the two microswitches inside the top latch receptacle...specifically the microswitch with the two parallel strips.

The fact that your problem is intermittent makes it even more likely that it is that switch as the solder joints on the strips are notorious for almost invisible hairline cracks. Those cracks sometimes make a connection again when the temperature rises (direct sun, closed car sitting in sun, etc.).

You can also double check fuses B6 and D3, and, if necessary, you may have to rule out a dead spot on the electric motor.

The "B-Pillar Microswitch" may also be involved, but that one controls the direction of the electric motor through the double relay in the kick panel.

Take a look at this thread for a similar problem and some additional details on the repair: http://986forum.com/forums/showthread.php?t=24128

Regards, Maurice.

[Artee]

Artee:

Congrats on your new ride! Drive it in good health!

Assuming that your parking brake idiot light is on (when you pull up on the parking brake) and that your windows drop down the 4 inches when you pull down the convertible top latch to unlock it, then your most likely suspect is one of the two microswitches inside the top latch receptacle...specifically the microswitch with the two parallel strips.

The fact that your problem is intermittent makes it even more likely that it is that switch as the solder joints on the strips are notorious for almost invisible hairline cracks. Those cracks sometimes make a connection again when the temperature rises (direct sun, closed car sitting in sun, etc.).

You can also double check fuses B6 and D3, and, if necessary, you may have to rule out a dead spot on the electric motor.

The "B-Pillar Microswitch" may also be involved, but that one controls the direction of the electric motor through the double relay in the kick panel.

Take a look at this thread for a similar problem and some additional details on the repair: http://986forum.com/forums/showthread.php?t=24128

Regards, Maurice.

Maurice-

Thanks for the advice, however, I am confused as to how the top latch microswitches could be the issue when it happens most often when the top is down. In fact, I was just out for a little bit, and checked the top down function, and it went down, and back up (I neglected to put it all the way down and then all the way up as I was worried if I put it all the way down it might not go back up). Could you explain how the receptacle microswitches would impair the top's "up" functionality? Is it simply built so that if the connection is loose the top doesn't function at all? Why would it matter, especially when the top has problems going up, and not down? Also, although the hot/cold temperature problem seems a likely candidate due to the intermittent function, the problem seems completely unrelated to temperature whatsoever, it has not worked when hot or cold, and has worked when hot or cold. For instance, the car was in my non-heated garage for over 12 hours, and the first thing I did when I started the car in the morning was to check if the top would go up, which it did not.

One of my friends suggested that the symptoms seem in line with a relay issue, which I will fiddle with tomorrow (check if it's loose, check the pricing on the part to see if it's cheap enough to replace). Still, now that the top seems to be working fine (it is cold tonight, must be around 40 degrees Fahrenheit), if I do replace it, and it still seems to be working right, but isn't the problem, I won't be able to tell until it's too late. If I do replace it, I may need to keep the top up for a couple weeks until I have enough money to fix the problem regardless of how difficult and/or expensive it might be, just in case it gets stuck down again.

Totally unrelated - the red light at the end of the oil temp gauge was blinking for the whole 20 minutes I just drove the car, I assume this means that I should check the oil, or the car needs an oil change, or some oil issue. The last one was done at 14,3XX miles, and the car now has 17,1XX miles on it, which seems very soon for an oil change. If you (or anyone else) know offhand what this is, and see this before noon EST Thursday March 25th, please let me know what it is, but it is 3 am, and although I have no work or classes tomorrow, it is really late and I'm too lazy to figure out what this is now, and will look it up in the owners manual tomorrow.

The biggest problem for me at the moment is that I am not on a payroll system, I am an intern, and get paid via invoices that I make and subsequently send to my boss, who checks them (to make sure I didn't add an extra 10 hours onto what I actually worked), and then sends them on to the payment folks of the parent company. For some reason, it takes a good 4+ weeks minimum for the first payment to come through. In the past, this has been completely random, and not knowing when I am going to get paid makes budgeting and saving money extremely difficult. Sometimes I get paid a few hundred a month, sometimes a hundred every other month, sometimes a couple grand every week. This is why I am happy my top is up now, so that if it does get stuck up, I don't have to worry about not being able to go anywhere on a rainy day, and I do not immediately need to fix this, so I have time to save up some money should there be a major problem.

Another unrelated issue - I have an '04 Kawasaki EX250 "Ninja" (the 1st generation baby Ninja), and once summer gets rolling, the bike and the drop-top will be hard to choose from.

[1schoir]

Maurice-

Thanks for the advice, however, I am confused as to how the top latch microswitches could be the issue when it happens most often when the top is down. In fact, I was just out for a little bit, and checked the top down function, and it went down, and back up (I neglected to put it all the way down and then all the way up as I was worried if I put it all the way down it might not go back up). Could you explain how the receptacle microswitches would impair the top's "up" functionality? Is it simply built so that if the connection is loose the top doesn't function at all? Why would it matter, especially when the top has problems going up, and not down? Also, although the hot/cold temperature problem seems a likely candidate due to the intermittent function, the problem seems completely unrelated to temperature whatsoever, it has not worked when hot or cold, and has worked when hot or cold. For instance, the car was in my non-heated garage for over 12 hours, and the first thing I did when I started the car in the morning was to check if the top would go up, which it did not.

One of my friends suggested that the symptoms seem in line with a relay issue, which I will fiddle with tomorrow (check if it's loose, check the pricing on the part to see if it's cheap enough to replace). Still, now that the top seems to be working fine (it is cold tonight, must be around 40 degrees Fahrenheit), if I do replace it, and it still seems to be working right, but isn't the problem, I won't be able to tell until it's too late. If I do replace it, I may need to keep the top up for a couple weeks until I have enough money to fix the problem regardless of how difficult and/or expensive it might be, just in case it gets stuck down again.

Totally unrelated - the red light at the end of the oil temp gauge was blinking for the whole 20 minutes I just drove the car, I assume this means that I should check the oil, or the car needs an oil change, or some oil issue. The last one was done at 14,3XX miles, and the car now has 17,1XX miles on it, which seems very soon for an oil change. If you (or anyone else) know offhand what this is, and see this before noon EST Thursday March 25th, please let me know what it is, but it is 3 am, and although I have no work or classes tomorrow, it is really late and I'm too lazy to figure out what this is now, and will look it up in the owners manual tomorrow.

The biggest problem for me at the moment is that I am not on a payroll system, I am an intern, and get paid via invoices that I make and subsequently send to my boss, who checks them (to make sure I didn't add an extra 10 hours onto what I actually worked), and then sends them on to the payment folks of the parent company. For some reason, it takes a good 4+ weeks minimum for the first payment to come through. In the past, this has been completely random, and not knowing when I am going to get paid makes budgeting and saving money extremely difficult. Sometimes I get paid a few hundred a month, sometimes a hundred every other month, sometimes a couple grand every week. This is why I am happy my top is up now, so that if it does get stuck up, I don't have to worry about not being able to go anywhere on a rainy day, and I do not immediately need to fix this, so I have time to save up some money should there be a major problem.

Another unrelated issue - I have an '04 Kawasaki EX250 "Ninja" (the 1st generation baby Ninja), and once summer gets rolling, the bike and the drop-top will be hard to choose from.

Artee:

Tough to maintain a Boxster in your circumstance, but if you can stay away from the dealer for this issue, you could manage it for not too much $$. :rolleyes:

You are correct in your guess that "if the connection is loose the top doesn't function at all" in one of the two microswitches inside the latch receptacle. That one completes a circuit to power the motor through the double relay. The other one controls (through the relay) the 4" window drop function.

It won't cost you anything to check the "parallel strips" microswitch, but you have to test it with a multimeter because any cracks in the solder joints are not easily visible.

If it's not that microswitch, then it's either one or more dead spots in the electric motor, or, more likely a problem with the double relay. Pull and push that relay on an off to clean off any corrosion on the terminals or use some emery cloth on the spades, and then give the relay a couple of sharp raps on a table to see if that restores it.

I mentioned the B-Pillar microswitch, which you should check out also, although that one (in conjunction with the black lever microswitch that is on top of the electric motor) regulates the direction that the motor spins the V-Levers.

Are you sure that the red blinking light is not the "coolant level low" light? If so, check the coolant level and investigate where any coolant may have gone. Not uncommon occurrence if the coolant system has not been bled properly of any air.

Regards, Maurice.

[Artee]

Artee:

Tough to maintain a Boxster in your circumstance, but if you can stay away from the dealer for this issue, you could manage it for not too much $$. :rolleyes:

You are correct in your guess that "if the connection is loose the top doesn't function at all" in one of the two microswitches inside the latch receptacle. That one completes a circuit to power the motor through the double relay. The other one controls (through the relay) the 4" window drop function.

It won't cost you anything to check the "parallel strips" microswitch, but you have to test it with a multimeter because any cracks in the solder joints are not easily visible.

If it's not that microswitch, then it's either one or more dead spots in the electric motor, or, more likely a problem with the double relay. Pull and push that relay on an off to clean off any corrosion on the terminals or use some emery cloth on the spades, and then give the relay a couple of sharp raps on a table to see if that restores it.

I mentioned the B-Pillar microswitch, which you should check out also, although that one (in conjunction with the black lever microswitch that is on top of the electric motor) regulates the direction that the motor spins the V-Levers.

Are you sure that the red blinking light is not the "coolant level low" light? If so, check the coolant level and investigate where any coolant may have gone. Not uncommon occurrence if the coolant system has not been bled properly of any air.

Regards, Maurice.

Thanks for clarifying, I didn't realize that the switch is part of the circuit. I will check it either today or tomorrow, as I will have to borrow the multimeter from someone.

And yes, it is the coolant level low indicator light. Thanks.

Edited March 25, 2010 by Artee

[1schoir]

Thanks for clarifying, I didn't realize that the switch is part of the circuit. I will check it either today or tomorrow, as I will have to borrow the multimeter from someone.

As I said, it would be helpful if anyone knew offhand what the blinking red light means, but I'm looking it up in the owner's manual now. It is possible that something happened to the coolant, as the engine seemed to warm up quickly while it was blinking. Thanks again.

Artee:

Just take a look inside the coolant tank after the car has cooled down, and be careful when you open the coolant cap. You should also be able to see the coolant level from the semi-transparent side of the tank, where the trunk carpet is cut out around it. If it's down, you will have your answer, and you can refill it with coolant or top it up with some distilled water. The red blinking light should then disappear.

Don't drive around with the red light flashing as it could overheat and/or cause hot spots in the engine.

Regards, Maurice.