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98 locking issue - please help identify these sounds

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Hi all,

Just picked up my first 986 and have spent the last week fixing as many of it's problems as I could ( clutch, lighting, top operation, misfire, to name a few)

I'm almost at the end of the tunnel but I'm stuck on the locking problem (hopefully the last repair) I've been reading up and figured that the locking mechanisms were the culprit & decided to investigate. The passenger door wouldn't lock at all so I started there, also assuming the lack of use may present a stuck micro switch.

Upon pulling it apart I found them to be operational, but noticed the small locking electric motor to have a seized rotor. I plugged the circuit card back in to the door and then decided to try the remote while at the same time operating the switch to signal the lock in position.

Needless to say it didn't help and it made the same noises as before. ( hope you can follow my process, I realize it's not the clearest) understandably it could also be a combination of both door locks, and will be pulling that one soon, but figured I would post a small video I took so someone experienced can identify what the controller is trying to do.

The noise is coming from the box under the seat. If the video attachment doesn't work, I'll try to describe it.

First noise when the button is pressed sounds like a small motor. The noise happens twice, is a second long, with 1/2 second in between. Then I get the same timing as before, only this time it is 2 clicks, like and probably is a relay. I get no horn sound & no flashing lights. The switch on the dash makes the same noises and does not light up. The carpet under the seat is dry, as is the control box.

Can someone please explain how the controller works - that way I should be able to figure out what the noises correspond to. I am not a fan of throwing parts at something and hoping for the best, is like to understand the system.

Thanks for your patience reading this! If someone could please help it would be greatly appreciated.

Thank you

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Make sure when you're testing the door lock that both doors are closed. You can trick the car into thinking they are closed by pressing the latch mechanism on the door with a screwdriver (as if it were hitting the door striker metal loop). If the windows are rolled up, they should raise 1/2" once you do this. Make sure you pull the handle to release the latch before you close the door again.

I don't know what those noises are. Just guessing, but the Boxster is supposed to flash the blinkers twice to signal that the doors are locked and the ticking noise could be the relay for the blinkers. I'm not sure what the whirring would be other than the door locks themselves...

It seems like the horn would beep when locking to signal the problem with the door locks. Maybe the previous owner disabled that feature after getting tired of hearing it.

Good luck.

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The noises are definitely coming from the control unit under the seat. I have just pulled it apart and had to shake my head when I saw the circuit card - yet more "repairs" the PO attempted in a shade tree way. See picture


The drivers side locking motor is also bad. There are no numbers on them to identify the exact ones - I wish there was, they are only $5 each normally.

At this point I think I'll just deal with the locking problem. By the time I've bought 2 locks & had the controller replaced & reprogrammed I'll be out quite a chunk of cash. My car is garage kept, and years of owning Jeeps have taught me to leave convertibles unlocked - I'd rather replace some loose change from the ashtray that a new top or glass window.

Edited by Shelby427uk
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  • 2 years later...

Hello to the forum members and Shelby427uk. The soldering on this PCB board has some short circuits on it and it is - new soldering. Also remove flux (The brown stuff left after soldering) with a toothbrush and some iso alcohol so the pcb is clean. See attached image.



All the best. 

Edited by King Kappa
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