I have a 05 Roadster, I had it parked all winter except for a few nice days I took it out and drove it but never put the top down. Two weeks ago I top quit working, then the door locks quit working which means of course the trunk won’t lock and my power seats don’t work, and my key fob will not lock or unlock the doors. I’ve checked all the fuses, yes the window still roll down when you engage the button to put the top down, never been driven on salty roads been parked in the garage for the last year and a half that I’ve had it, I’ll check the hydraulic fluid and filled it and still nothing! I’ve check the switch on the passenger side top and I don’t know where to go from here, maybe it’s time to just sell the car 😩

 

Could be as simple as a new battery. These cars are very finicky when it comes to batteries.

 

So even though the car starts fine it could still be the battery? Dumb question but I’m running out of patience with this thing!!

 

Yes. In 1965, the battery's job was to deliver 350 amps of current for a SHORT time to get the car started -it's job was then done and the alternator restored the battery's charge.

Today, it is an entire new world. Today, the battery has a second job, that of capacitive filter. That is, it is called upon to act as a huge capacitor, providing CLEAN power to all the modules and systems in the car.
The DC electrical supply in a car is a hostile environment in which to put sensitive electronics that are based on LSI and VLSI (large scale and very large scale integrated electronics).

As the battery ages, its ability to deliver enough current to start the car degrades. But what degrades faster, is the battery's ability to filter.

 

Thanks for the info! I’ll try replacing the battery and let ya know! 👍

 

This is just too much to diagnose remotely. Let's take some of it apart:

1) The power seats are a SIMPLE system, devoid of any electronics, they are simply electric motors run by a system of switches and relays. The most common issue is the little circuit on the "Power Seat Relay" that suffers from fractures in teh solder on the parts on the board. A new seat relay costs around $30 and plugs in. I don't see how power seat issues are related to anythign else.

2) The door locks, lock-unlock and top issues are likely related to one another. This is where the idea of a new battery enters the picture.

Also, one would perhaps want to question WHERE this car was stored. Did you have it in a horse barn? (I'm not being snotty.) We've seen 'barn stored' cars with chewed up wiring, thanks to the rodents that bunk with horses or cattle. If this is the case, burn the car with fire and file for insurance. (Seriously, some here will be willing to help you, not me. Life is too short, sorry.)

Is there ANY chance of water intrusion in the rear wheel wells or trunk area? This would explain every issue other than the power seats (and I've already said I dont' see the power seats being part of the rest of this). Tear the liner and trim out of the trunk and look for water intrusion in the wheel wells and trunk cavities. Just verifying that there IS no water damage would be helpful. WHile in there, look for chewed wiring or rodent droppings. If you see signs of urine or droppings, remember, suicide is always an option - way easier than fixing rodent damage.

If you can't find any of the above (no water, urine or droppings; no chewed wiring), we have more detective work to do. If all this has one cause, and it is not rodent or water-damage related, this is going to be something so simple it's going to make you mad in the end. Problem is, getting to that end may be a long, frustrating task. But fact is, it will turn out to be something stupid.

 

Ok, done editing...........

 

I’ve had the car in my garage with heat so no rodents problem. I pulled the rear trunk panels out when I was checking the hydraulic fluid and there’s no water at all in the trunk area or any type of watermarks so that’s not the issue. As far as the seats go I’ll check into what you said and see if I can’t find something it’s just odd that one day they worked and the next day they didn’t. I’ve had the car for a year and a half and have only put 2000 miles on it. Appreciate your help and your input and you’re correct that if there was rodent damage the car would disappear in a hurry.

 

I did have a thought. The power seats COULD be related to this, IF the entire issue is a shorted cell in the battery or something similar.

Go out to the car, pop hood.

Grab a multimeter and measure the voltage across the battery. Record the reading. (SHould be 12.2 to 12.5 volts)
STart engine.
Repeat the measurement. Record the reading. (Should be 13.5 to 14.2 volts)

Post both readings here.

 

12.4 and 14.3

I was really hoping that the battery would be the issue but I guess not

 

Now you can be assured the alternator is charging. YOu can be reasonably sure the battery is OK, but this does not PROVE The battery is OK, the only way to do that is to substitute another battery.

 

Well I will give that a shot this week when I go to my other shop and let ya know!

 

Was your issue resolved? What was causing the problems? New owner here with issues and searching the forum and found your thread..