Central locking

For all those wiring gremlins we love, this is the place to discuss them.

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lambert.john
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Central locking

Post by lambert.john »

Hi, guys. My central locking has failed and I am having to lock driver and passenger doors separately. Locking and unlocking the driver's door I get the familiar "whirr" of the motor; locking and unlocking the passenger door I don't. Before I start dismantling things I would be most grateful for any suggestions.
John L.

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amarshall
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Re: Central locking

Post by amarshall »

Do you get the same noise from the passenger door when you lock/unlock it?
What happens when you use the interior lock handles rather than the exterior locks?

(I've spent a lot of time on the CDL system over the years, if it's OK with you, I'd rather walk through some tests than just post it all and hope you find the problem by chance).
https://www.lotusexcel.co.uk/
SORN - just say NO!

lambert.john
Senior Poster
Posts: 263
Joined: Fri Nov 04, 2005 20:57
Model: SA
Colour: Blue
Year: 1987
Location: Luton, Bedfordshire

Re: Central locking

Post by lambert.john »

Thanks, Angus. I always get the motor "whirr" when I lock/unlock the driver's door; I never this noise locking or unlocking the passenger door. This is the same whether I'm using the key (from the outside), or the interior handles (from the inside).
John L.

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amarshall
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Re: Central locking

Post by amarshall »

OK - I think the starting point will have to be the passenger door. You need to check if the CDL actuator is actually present and connected, then see if it triggers when you pull/push the rod connected to it.

If it's never worked, I'd guess that a PO disconnected it because the rods are out of adjustment and you'll need to spend some time adjusting them to get it to work perfectly. It is possible - see here for some hints: viewtopic.php?f=8&t=10072

If it does respond to manual movement of the rod, but the other one doesn't trigger with it, then the chances are there's an electrical fault between the two actuators so you'll need to check the voltages on the wires feeding into to.

Correct voltages are in this thread : viewtopic.php?f=27&t=10840&hilit=cdl

If they're all present and correct, it's probably a faulty actuator or earth.

If you just have one of the connecting wires broken, then the non-actuating actuator will force the other one to switch back to the starting state after you unlock it, so it's unlikely to be a single broken wire (unless a PO has disconnected the passenger CDL because a single wire fault was causing the car to lock as soon as it was unlocked).- but could be failure of both (or the common earth) in the loom.
https://www.lotusexcel.co.uk/
SORN - just say NO!

lambert.john
Senior Poster
Posts: 263
Joined: Fri Nov 04, 2005 20:57
Model: SA
Colour: Blue
Year: 1987
Location: Luton, Bedfordshire

Re: Central locking

Post by lambert.john »

Many thanks, Angus; that gives me a good steer!
John L.

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