Rear wiper stopped working

[Metallo]

Hi All,

After 27 years, my rear wiper stopped working, on both intermittent and regular positions.

No previous sign of slowing down or whatsoever

Here is what I did so far, in chronological order:

1) I checked the fuse (#14), all good there.
2) I disassembled the whole assembly, motor and wiper arm.
3) Tested the connections, and I got 12V on all fronts
4) Disconnected the wiper arm from the motor
5) Re-plugged in the 3 connectors:tested the motor and it spins, both regular wiping and intermittence.

Now, one thing that I hate is to re-assemble everything and pretend nothing happened.
Obviously there is a reason why it stopped working out of the blue, but I simply cannot identify it.

I checked the wiring, but everything looks good, it is all very clean in that area. In fact, I never needed to remove the tailgate interior panel before.

I thought I might take the opportunity to open the motor, clean and lubricate it, but I have no clue how to open it as I see rivets

I attach some images I just took.









For instance, in image one, it seems that the circular clip around the central axis is the one holding the mechanism cover. If you look at image three, the cover is slightly open, which leads me to think that clip keeps that in place.

I cannot find any guide on how to open this motor, do you have any?

Thank you for your help!

Alessandro

[J liddy]

Hi someone will be along shortly hopefully to help hopefully .a guy Forrest is very clever with small moters on here worst scenario someone will have one for sale too hopefully

[GingerMagic]

I'm no expert by any means, but did you try the rear wiper with the tailgate open as well as closed?

Possibly a broken wire in the flexible conduit?

[john.wigley]

Originally Posted by GingerMagic

I'm no expert by any means, but did you try the rear wiper with the tailgate open as well as closed?

Possibly a broken wire in the flexible conduit?

More than possibly, 'G.M.'. Given the comprehensive action 'Metallo' has already taken without success, I would say it was a racing certainty and put money on It! This was a known problem on earlier cars and Volvo introduced a more flexible multi strand cable, which mitigated, but did not completely cure, the problem.

The point of failure is not particularly time related, but does correlate directly with the amount of use that the tailgate has seen, and it is possible to splice in a cable to solve the problem.

As an aside, this issue may also extend to the licence plate lights, HLBL and locking mechanism, but it is the wiper that seems to be most likely to fail in this way.

Regards, John.

[Metallo]

Originally Posted by GingerMagic

I'm no expert by any means, but did you try the rear wiper with the tailgate open as well as closed?

Possibly a broken wire in the flexible conduit?

Hi GM,

Yes, I did that too, multiple times, and everything works as expected.

[Metallo]

Originally Posted by john.wigley

More than possibly, 'G.M.'. Given the comprehensive action 'Metallo' has already taken without success, I would say it was a racing certainty and put money on It! This was a known problem on earlier cars and Volvo introduced a more flexible multi strand cable, which mitigated, but did not completely cure, the problem.

The point of failure is not particularly time related, but does correlate directly with the amount of use that the tailgate has seen, and it is possible to splice in a cable to solve the problem.

As an aside, this issue may also extend to the licence plate lights, HLBL and locking mechanism, but it is the wiper that seems to be most likely to fail in this way.

Regards, John.

I am out of options, so I will have to reassemble and wait for the next time it stops. Honestly, I doubt it is a wire issue, as I mentioned everything is clean and tight, and considering this car is from 1997, they probably fixed that issue by then.

Of course, this is only my opinion, but those are not micro wires like a laptop flat connector, and I do not see any critical area where they may be squeezed.
Opening and closing the tailgate is not something I do every day either.

I only wish I could open the motor because, eventually, I'd see a higher possibility of a dirty connector inside or maybe the brushes reaching their end of life, rather than a bad wire elsewhere.

Thank you,
Alessandro

[Metallo]

Hi folks,

I cleaned and re-assembled everything, and what happens is that when I tight the nut holding the wiper arm to the motor and start the motor, I can hear the impulse of the motor, but it is like the arm cannot move.

The motor works fine if I disconnect the arm.
I cannot understand what prevents the arm to make its movement, everything looks good, including the splines.

I wonder, it this supposed to have this play, or should it be pushed inside?



More images, the arm looks absolutely fine, but clearly, something mechanic happens when the arm is in place, preventing the natural movement it is supposed to make.





Thoughts?

Thank you!

Alessandro

[J liddy]

If the moter works you are nearly there so it's a case of eliminate each part
I've had that rear wiper size up twice now due to build up of dirt and grime around the outer spindle shaft was the problem it takes a bit of tie to remove the moter then put everything back together but job satisfaction when it's back together

[Simmy]

rear wiper problems are usually spindle seized and the motor has stripped the teeth off the internal gears or if no power to the motor fuse or break in the wire inside the car near the hinge conduit its also worth checking the relay but these hardly ever fail

[Metallo]

Originally Posted by J liddy

If the moter works you are nearly there so it's a case of eliminate each part
I've had that rear wiper size up twice now due to build up of dirt and grime around the outer spindle shaft was the problem it takes a bit of tie to remove the moter then put everything back together but job satisfaction when it's back together

Given that the motor works, the only other spindle is the one of the wiper arm. (my image at the bottom of my previous post)

Are you saying that it can get seized? It is pretty clean, and splines are perfect.

Can it be opened??

Alessandro