1998 S70 Door Lock Actuator Issue?

Post by **bmdubya1198** » 20 Oct 2015, 10:32

ferocity02 wrote:Thank you for the replies everyone!

I forgot to add one key piece of information. The door will LOCK just fine with the key AND buttons. But it will not UNLOCK with the buttons. It will only unlock with the key.

Does this change what could be wrong?

I don't think so. Mine does the same, and my cousin's does as well.

Post by **cn90** » 20 Oct 2015, 12:34

The electric motor inside may allow it to spin in one direction (Lock), but not the other direction (Unlock using remote).
Usually the tiny Mabuchi motor is the culprit.

Blockpartie · Post by **Blockpartie** » 20 Oct 2015, 12:57

Test if after unlocking it with the remote the door can be opened by the inside handle.

Post by **BEJinFbk** » 20 Oct 2015, 14:54

There are two ways to unlock these doors.
Manually, with the key or the knob or
Electrically, with the switches or remotes.

Whether you use the switches or the remote
makes no difference to the electrical operation.
The motors are still operated by the same relays in the
keyless entry module, regardless of the input trigger.

As far as the Lock/Unlock function, it's pretty dang likely that
different amounts of torque are required for each operation.
In fact it'd be a mighty strange coincidence if they DID use
the same amount of force. Just sayin'.

Post by **BEJinFbk** » 20 Oct 2015, 14:58

cn90 wrote:If you want to remove the worm gear, see the link below: basically heat gun and a little tap with hammer:

http://www.northamericanmotoring.com/fo ... ement.html

I don't get why you'd go after the motor without
checking out that little protection resistor first.
To me, that's kinda like rebuilding an engine
before checking out the fuel pump.
And you don't need to buy anything to do it.

ferocity02 · Post by **ferocity02** » 25 Oct 2015, 17:13

I pulled the door panel off and I can see that the actuator is moving (with complete range of motion) when I press the unlock button. This means that the motor is working. But for some reason its not actually unlocking. I spent a good half hour studying the actuator device but its very complicated and hard to see anything. I have no idea why it's not working.

Post by **cn90** » 05 Dec 2015, 08:16

I have the EXACT same issue on the Front Pass Actuator.

- Hit the remote to open doors, all 3 doors open except Front Passenger door knob (it stays locked).
- From driver's seat, reach over and pull it up manually...no problem.
- Hit remote to lock the doors, all 4 knobs go down: no issue.

So do the gurus think it is the "protector resistor" issue.

PS: BTW, this very (Front Passenger side) actuator was replaced using Volvo Genuine part some 5 years ago, what a waste of $120!

Blockpartie · Post by **Blockpartie** » 05 Dec 2015, 08:46

Try to use the inside handle to open the door when the pin / door knob / what ever you want to call it is still in the "locked" position.

darylrobert · Post by **darylrobert** » 05 Dec 2015, 22:05

had the same issue, basically the little motor dies after years of operation, theres a spring that I removed which made life easier for the motor for a while but it soon stopped working al together. just replace the lock assembly

Post by **cn90** » 05 Dec 2015, 23:32

OK,

So can some smart engineers explain me something?
I don't think my electrical motor is dead (or the resistor is dead), this is b/c when:
1. I hit the remote, only 3 door knobs come up. The Front Pass side stays down (locked position).

2. So I reach over and lift the knob upward. Then hit remote to close: all 4 doors close properly.

If my electrical motor is dead, it would be dead both ways (up and down).
If the resistor is dead, I expect the same, i.e., the knob will not go up or down.