PROBLEM WITH RECTRACTING REAR HEADRESTS

[r44raven]

The headrests will no longer retract to the lowered position.

I have located the solenoid beneath the driver's side rear seat. With the ignition switch "on", this does not "click" when the retracting button is pressed (I assuming here that the solenoid would operate with the ignition "on" but the engine not running?).

Also, with the engine running, if I remove the "inlet" side vacuum pipe from the solenoid, there doesn't appear to be any vacuum suction on this pipe.

(In all cases, the rear blind is fully retracted).

Am I chasing two problems here, i.e. no vacuum supply to the solenoid, plus also an inoperative switch?

Any ideas, anyone?

Thanks in advance.

 

[gsxr]

It does sound like multiple issues. With the engine running, you should get vacuum at the supply tube.

The headrest switch should be checked, and as you noted, the roller blind must be 100% retracted or the switch will not energize the vacuum solenoid.

Also, the switch must be held down for 1-2 seconds with the engine running, for the headrests to drop.

 

[nocfn]

what if the blind is removed altogether, and you cannot get yours to move.

 

[gsxr]

You can manually drop the headrests by applying vacuum to them with a MityVac, or a long hose connected to the intake manifold with the engine running. That bypasses the switch and solenoid.

 

[nocfn]

But with the switch, that should work right? With the car running?

 

[r44raven]

It does sound like multiple issues. With the engine running, you should get vacuum at the supply tube.

The headrest switch should be checked, and as you noted, the roller blind must be 100% retracted or the switch will not energize the vacuum solenoid.

Also, the switch must be held down for 1-2 seconds with the engine running, for the headrests to drop.

A couple of questions for clarification. Am I correct that the solenoid should "click" when operating, and this should happen with the ignition on (but the engine not running)?. I guess the fault here could be the solenoid, or the central console switch itself - or indeed the switch which senses whether the rear blind is at its lowest position?

Also, as I'm not getting any vacuum on the supply side of the solenoid, where do I start to find the reason for this? The vacuum pipe disappears somewhere beneath the floor, and would be difficult to trace for leaks? Does it lead directly back to the vacuum pump, in which case it might be easier to just install another pipe and bypass the existing one - or am I simplifying things too much?

 

[gsxr]

A couple of questions for clarification. Am I correct that the solenoid should "click" when operating, and this should happen with the ignition on (but the engine not running)?. I guess the fault here could be the solenoid, or the central console switch itself - or indeed the switch which senses whether the rear blind is at its lowest position?

Yes, it should click, but I can't recall if it is loud enough to hear from the front seat, or if you need to have your fingers on it to feel the click.

Also, as I'm not getting any vacuum on the supply side of the solenoid, where do I start to find the reason for this? The vacuum pipe disappears somewhere beneath the floor, and would be difficult to trace for leaks? Does it lead directly back to the vacuum pump, in which case it might be easier to just install another pipe and bypass the existing one - or am I simplifying things too much?

I'd start at the vacuum supply lines, which should be above the brake booster area. The system rarely leaks, but another vacuum consumer can cause a leak. Example: One of my 124's had no footwell airflow with the heat on. Turned out to be one of the headlight vacuum actuators failed and was leaking vacuum, causing the HVAC flaps to not function. Not sure if something like that is what you are dealing with, but keep it in mind...

 

[r44raven]

Yes, it should click, but I can't recall if it is loud enough to hear from the front seat, or if you need to have your fingers on it to feel the click.




I'd start at the vacuum supply lines, which should be above the brake booster area. The system rarely leaks, but another vacuum consumer can cause a leak. Example: One of my 124's had no footwell airflow with the heat on. Turned out to be one of the headlight vacuum actuators failed and was leaking vacuum, causing the HVAC flaps to not function. Not sure if something like that is what you are dealing with, but keep it in mind...

Thanks v much for that comprehensive reply!

I'm away on a road trip with the car at the mo, so won't have a chance to continue my investigations till I get back after the weekend.

But i'll keep you posted.

 

[Efraim]

Are there any WIS sheets for rear headrests? I haven't found any.

 

[r44raven]

Are there any WIS sheets for rear headrests? I haven't found any.

Somewhere in my files I have some instructions on how to remove the rear headrests and the rear shelf. When I get back from my road trip at the weekend, I'll try and look them out.

 

[Efraim]

Somewhere in my files I have some instructions on how to remove the rear headrests and the rear shelf. When I get back from my road trip at the weekend, I'll try and look them out.

I have the same document (68-0458) but it doesn't say anything about function of retracting headrests.

EDIT:
I found this instruction, it is original WIS doc but with very bad scanning quality.
Installation Procedure For Rear Seats Headrest

 

[r44raven]

I have the same document (68-0458) but it doesn't say anything about function of retracting headrests.

I think you're probably right, but i'll still look out the papers to check what it covers.

 

[r44raven]

I think you're probably right, but i'll still look out the papers to check what it covers.

I've looked out those papers - all I have is the same as you, i.e. 68-0458 - which details removal of the headrests, but no information on problem solving!

 

[r44raven]

I'd start at the vacuum supply lines, which should be above the brake booster area. The system rarely leaks, but another vacuum consumer can cause a leak. Example: One of my 124's had no footwell airflow with the heat on. Turned out to be one of the headlight vacuum actuators failed and was leaking vacuum, causing the HVAC flaps to not function. Not sure if something like that is what you are dealing with, but keep it in mind...

I found the problem. The vacuum supply to the "4-way" connector above the brake booster had become disconnected. (I've only recently had the car serviced, and wonder if it had been disturbed somehow by the tech doing the work?).

Anyhow, the headrests now retract.

However, when reconnecting the vacuum to the supply side of the 4-way connector, the connections to the outgoing feeds easily came apart. The connections were not very tight, as if it could all readily disconnect again! I'm wondering if I should source a new connector? Any idea of the part number, anyone (I'm attaching a pic of the offending item!)?

Lastly, a bit of info that might prove useful. If testing the solenoid switch (situated under the driver's side rear seat) which controls the vacuum supply that retracts the headrests, the engine must be running. The switch will not operate with just the ignition on.

 

[gsxr]

Sweet! Glad it was an easy fix! And, I did not know the engine needed to be running to energize the solenoid. Good info.

The 4-way rubber splitter should be 601-078-05-45, about $14 MSRP here in the colonies. Appears to still be available.

 

[Surf Blau]

I found the problem. The vacuum supply to the "4-way" connector above the brake booster had become disconnected. (I've only recently had the car serviced, and wonder if it had been disturbed somehow by the tech doing the work?).

Anyhow, the headrests now retract.

However, when reconnecting the vacuum to the supply side of the 4-way connector, the connections to the outgoing feeds easily came apart. The connections were not very tight, as if it could all readily disconnect again! I'm wondering if I should source a new connector? Any idea of the part number, anyone (I'm attaching a pic of the offending item!)?

Lastly, a bit of info that might prove useful. If testing the solenoid switch (situated under the driver's side rear seat) which controls the vacuum supply that retracts the headrests, the engine must be running. The switch will not operate with just the ignition on.

View attachment 237147

I've had similar experiences with the rubber tube "connectors" for the vacuum lines, after x years they become harder and do not seal and grip satisfactory. I don't think it's a huge problem in an area where they are left alone, but as you've discovered it doesn't take much for them to come loose, and if they do it might affect other components.

I do have a bunch of these "connectors" from various parts cars though, and even though they are all pretty much the same age there are huge differences in how they behave. Not sure if excessive heat and/or pollution could cause the hardening?