central locking problem

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Binns
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Post Sun Feb 18, 2018 9:44 pm

Hi all

All of my central loocking went dead.. took it all apart and all was locked like they where in dead lock mode, even the fuel cap lock

I took them all out and all are not moving or just sticking, are they in need of new ones?

also the control unit blew that fuse thats built into to it.

Cheers for any help

Btw it is a 2 door if that helps
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BenHar
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Post Sun Feb 18, 2018 10:06 pm

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Brianmoooore
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Post Sun Feb 18, 2018 10:14 pm

Any sign of water contamination in the locking ECU (control unit)?
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Binns
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Post Sun Feb 18, 2018 10:23 pm

no water damge that i could see.

i did try my mates ecu and lock (just drivers side) and worked ok with his, but the rest wouldnt open. the fuel cap one was frozen (locked) then i took it out no movement what so ever, passenger one just clicked and seemed like it wanted to go but nothing.. all very stiff or locked like dead lock.

old age and cold weather i guess
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Brianmoooore
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Post Sun Feb 18, 2018 10:43 pm

There's no dead lock motor in the lock motors of either the driver's door of the fuel flap, so if these are jammed, then it's likely they have been cooked by the ECU powering them for too long. This also ties in with the failed thermal fuse inside the ECU.
This usually occurs as a result of the ECU being flooded as a result of blocked sill drain slots, but you say yours appears dry. Not sure if this is good or bad (assuming motors are cooked), as it means you don't have a reason. I'd be wary of using the ECU again, although the link can be resoldered as long as you don't add any 'normal' solder. The original is a special low melting point mix.
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Binns
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Post Sun Feb 18, 2018 10:59 pm

Brianmoooore wrote:There's no dead lock motor in the lock motors of either the driver's door of the fuel flap, so if these are jammed, then it's likely they have been cooked by the ECU powering them for too long. This also ties in with the failed thermal fuse inside the ECU.
This usually occurs as a result of the ECU being flooded as a result of blocked sill drain slots, but you say yours appears dry. Not sure if this is good or bad (assuming motors are cooked), as it means you don't have a reason. I'd be wary of using the ECU again, although the link can be resoldered as long as you don't add any 'normal' solder. The original is a special low melting point mix.
Thanks alot thats what i thought all jammed and blew the ecu safe low temp soilder.
Any info on what the melting point is? i will try and re soilder it with the old soilder thats still on it and see what happens.

Thanks
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Brianmoooore
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Post Sun Feb 18, 2018 11:15 pm

Binns wrote: Any info on what the melting point is?
I don't, but lead/tin solder containing bismuth or indium can go down to around 100 degrees Celcius.