Today in my ‘shop. R230 SL, boot open warning

[Uncle Benz]

Quick one today. I haven’t seen this one covered, so here goes. Customer delivered car with complaints of boot open warning while driving. Initially stopping, opening and closing the boot would sort it, but it just got worse and worse. I parked the car next to a RangeRover to make it feel more reliable. (Damned with faint praise...).

The vacuum pull down was perfect evertime. No timeouts stored in the PSE. Boot was obviously closing correctly. Checked out the wiring running down the right hand boot hinge. All good. In this case the problem was in the boot latch microswitch. I’ve done a few of these. A lot of places will sell you a complete latch assembly. That’ll fix it, but you don’t need to spend £300. The rotary tumbler microswitch is available as a separate piece.


It fits here in the latch. You lift a little locking tab and just pull it out.


Quick and easy job. You’ll need to remove the boot liner trim panel, easiest with the roof down. The latch is held in with two torx screws. One vacuum pipe to remove, two electrical plugs and a clip that holds the emergency release bar.

 

[Blobcat]

Copied to DIY Here

 

[bluesl]

For what it's worth, my Range Rover Sport has been much more reliable than my R230 SL55 AMG which has been shockingly unreliable all through its life and currently has a number of difficult to diagnose issues.

What do we know about the PSE overrunning after the boot lid self-closes? Mine works fine but continues to run long after the boot lid has closed until the PSE pump calls time and shuts down, requiring a power cycle to restart it. People talk about leaks in the boot latching mechanism but I cannot see or hear anything wrong. The air pipe only ever blows and there is a diverter valve which is set to activate either the small release actuator (the circular thing at the bottom of the picture) or the self-close actuator which is at the back of the mechanism in the picture. I assume there is a problem with one of the solenoid valves in the PSE and my car is going into the SLShop for them to run the diagnostics.

 

[LostKiwi]

For what it's worth, my Range Rover Sport has been much more reliable than my R230 SL55 AMG which has been shockingly unreliable all through its life and currently has a number of difficult to diagnose issues.

What do we know about the PSE overrunning after the boot lid self-closes? Mine works fine but continues to run long after the boot lid has closed until the PSE pump calls time and shuts down, requiring a power cycle to restart it. People talk about leaks in the boot latching mechanism but I cannot see or hear anything wrong. The air pipe only ever blows and there is a diverter valve which is set to activate either the small release actuator (the circular thing at the bottom of the picture) or the self-close actuator which is at the back of the mechanism in the picture. I assume there is a problem with one of the solenoid valves in the PSE and my car is going into the SLShop for them to run the diagnostics.

Always a leak in the pipe to the lock or the lock assembly. Have you tested it with a vacuum tester?

 

[bluesl]

Always a leak in the pipe to the lock or the lock assembly. Have you tested it with a vacuum tester?

Yes, pumped it up to 3 bar from where it connects to the PSE and left overnight. No loss of pressure.

 

[alexanderfoti]

The internal pressure sensor in the PSE pump is dead then. See it quite a lot with water damage. They just run and run and run until timeout, but with no leaks.

 

[bluesl]

Can that be repaired or is it a new PSE pump? I guess it’s over £1000…

 

[alexanderfoti]

Can that be repaired or is it a new PSE pump? I guess it’s over £1000…

Sometimes they can

 

[Uncle Benz]

David Arnott is your man. I’m sure he’s a member on here. He reconditions PSE units. He’s helped me out a lot

 

[Uncle Benz]

https://forums.mercedesclub.org.uk/index.php?members/david-arnott.31470/

 

[bluesl]

Thank you for your help.