06 S60 rear headrest won't flip down Topic is solved

[mrbrian200]

I say lube - specifically a silicone grease that will stay put when things get hot. Such as Superlube Silicone formula.

***This could also be a symptom of resistance to ground, the solenoid would get 'weak'. It's one of the ring terminals on that side underneath the rear seat bottom (can't tell which from the diagram, there's more than one ring terminal attached to the chassis under there in that general area. Each headrest has it's own ground path on it's respective side under the cushion. According to the diagrams, the ground ring that this goes to is shared with grounds to other equipment via a junction point up in the harness. So probably best to disconnect the battery.

Edit. If the feed comes through that row of connectors under the edge of the seat bottom, resistance could be in the + feed if somebody has ever spilled a large sugary drink back there. That row of connectors is in a precarious spot where spills or an open rear window during a heavy rain might cause problems with those electrical connectors and the ground terminals nearby under the seat bottom. That business probably needed a plastic cover or something to channel spills/liquids around and under them instead of potentially into them. I saw this once when I had the seat bottom out and covered/wrapped the whole thing with press and seal wrap in an attempt to prevent the inevitable. I soldered over the wire crimps to the ring terminals and used conductive grease to keep liquids from wicking into the bolt/threads that attach to the chassis. Call me anal retentive...

[BlackBart]

Folks, this is sarcasm on my part, seems that eluded some. Iowa has bumpy edges.

Well it has two flat sides and two bumpy sides, and it is touching the square states.

Good luck on your fixit and I apologize for the distraction (although it was fun!).
Is there a catch that lets go of the spring-loaded headrest when the circuit closes, and it's not moving when under load or pressure? Like just a simple lube issue? Can you get it to click then release without the headrest up?

[EngineeringBloke]

There is a good thread on this, here, and lubrication is recommended:

https://volvoforums.com/forum/volvo-s60 ... oke-61336/

[erikv11]

Yeah, that's the same how-to that is linked in the first post. It's pretty useful once you have the headrest down, which I do now.

Ring terminals were all sparkly clean when I inspected them but I will give them a closer look with battery disconnected, thanks for the tip about a weak ground. And lube it. Will take a few days need to tend to other things first.

No worries Bart, I appreciate the full range of your comments!

[BlackBart]

The offending solenoid works fine to move the latch when there is no tension (while the headrest is manually "flipped down"), but fails to release the latch when the headrest is up, with tension on the latch.

Oh, oops, I missed this - you've already checked that.

[erikv11]

Summary of the solution: How to manually flip down a stuck, electronically released headrest:

The tools are a small hex key, a corresponding socket, and a nut driver, put together like this:

hex key, socket and nut driver

hex key assembled

You want to squeeze the allen key under the headrest and into the gap between the headrest post and the center trim:

Inserting assembly under headrest

Assembly under headrest and ready to turn

Then rotate the nut driver counter clockwise, this presses on the latch and releases the headrest forward:

Just after releasing the headrest latch

trim rings from the top

Now to fix it I removed the 2 plastic trim rings

trim rings removed

And opened up the seat leather.

seat leather opened up, ready to apply lube to the latch

Then without removing the mechanism I reached through the plastic holes and applied silicone lube onto the latch. It's been working great now, nothing else was needed. I didn't touch the grounds, they were all clean.

[abscate]

Well done. Have to think how to get this tagged.