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Can a faulty roof control module RVC or hydraulic fluid in switches or connectors cause S117 fault codes? Did I install a used faulty S117 limit switch? Why does the S114 limit switch activation cause S117 fault codes? Note that the (2) S117 codes popped up several times before I noticed the S114 activation also causes them to pop up. The same (2) codes popped up before I installed the new used S117 switch.
These (2) codes keep popping up after I erase them:
B1264-001
Stored&Current
S117 (Loading assist raise/lower limit switch) :Limit switch 'UP' not operating or has Cable break.
B1264-018
Stored&Current
S117 (Loading assist raise/lower limit switch) :Limit switch 'DOWN' remains in the switched status (contact sticking) or has Short circuit to ground.
A code from the S114 has popped up infrequently:B1190-002 Stored
S114 (Load assist switch) :Actuation of the orientation lighting has Short circuit to ground.
The roof is stuck down and locked. It will not ever even budge even after I clear fault codes when I activate the top up down center console switch. Hydraulic fluid has sprayed onto the trunk and hydraulic pump wiring. Fluid sprayed out of the hydraulic pump fill plug hole as I hopefully eliminated any air lock by using a syringe to pressurize the pump until bubbles quit perking out of the fill plug hole long ago and again just recently.
How can I get the top working again?
There is not such thing as the pump air locking. Your S117 switches, new and old, are probably both fine. The codes you are getting are because the roof didn't move when you hit the easypack button. If the control has commanded the roof to go to easypack position, for example, it has not way of knowing if it actually moved other than the limit switches. After some time period, it will expect the load assist down switch to open and the load assist up switch to close. This is not happening, so you get the codes. You should not get these codes when trying to close the roof with the console switch.
Exactly what happens when you try to close the roof? Does the pump run, windows move, anything? What about trying to raise the roll bar, does it do anything?
There is not such thing as the pump air locking. Your S117 switches, new and old, are probably both fine. The codes you are getting are because the roof didn't move when you hit the easypack button. If the control has commanded the roof to go to easypack position, for example, it has not way of knowing if it actually moved other than the limit switches. After some time period, it will expect the load assist down switch to open and the load assist up switch to close. This is not happening, so you get the codes. You should not get these codes when trying to close the roof with the console switch.
Exactly what happens when you try to close the roof? Does the pump run, windows move, anything? What about trying to raise the roll bar, does it do anything?
Thank you Mike! I hear the pump running when I activate the center console roof switch or the rollbar switch, or the easy pack switch. The rear quarter windows drop down a little when I push the roof up center console button. The trunk lid and rollbar do not move at all. The roof is stuck in the locked down position.
I have printouts of actual values using my Autel Diaglink, and don’t see anything suspect. I have the Mercedes official Star Diagnostic laptop and multiplexor based system, and can use DAS.
The first thing I would suspect is that the pump is not building pressure. You should be able to hear it loading up as it builds pressure. Start by checking the bypass valve. If it is tight, check the screw. Sometimes they get overtightened and damaged. I would suggest manually closing the roof to make access to the pump easier.
What is the history of the problem? Have you replaced parts other than the S117 switch? Did it start to work slowly, then quit? Anything you can add would help troubleshoot.
I had Top Hydraulics to rebuild the pump last, and all the roof cylinders over the past 5 years except the lock pawls for the rollbar. I put new u-cup rings in the lock pawls. I put way too much stop leak in the system about 5 years ago, and pumped out fluid through the lock pawls, and replaced fluid when I had cylinders rebuilt over the next few years. I suspect that some of the rebuilds have internal seal bypass leaks due to the stop leak.
I had the pump rebuilt lastly before I installed the new used S117. They installed a new non-original equipment pressure relief screw during the rebuild. Right after the pump rebuild the roof went up and down a few times, then it got stuck in the down lowered position. The trunk lid then would raise its leading edge a few inches and get stuck. The trunk lid would not close back down using the center console switch. I latched the top frame down locked, and it is stuck down latched, and will not move.
Note that after the pump rebuild and roof got stuck down Klauss had me to send the pump valve block to him which he tested good in his vehicle at top hydraulics. After I reinstalled the valve block IIRC the leading edge of the trunk would raise just a few inches and stop like it did many times before. Like earlier the trunk lid would not lower and lock down in the open position. I manually latched the roof frame lock latches with the allen key from the Mercedes supplied tool kit.
I would start by checking if you are holding pressure on line 100, the rod end of the roll bar cylinder. Actuate the pump with your scanner, this will provide pressure only to line 100. Stop the pump, and then slowly back off the retaining plate and see if line 100 is under pressure. You could probably also do this by measuring amp draw on the pump, or just listening to it. If you are getting higher amp draw or the pump motor is straining more when the pump is started with diagnostics, your bypass is probably one of the frame locks, the front latch, or the trunk lift. If you don't build pressure on line 100, you probably have bypass through the roll bar cylinder.
I actuated the pump for a few seconds with the scanner, loosened the retaining plate actuated again, and significant fluid came out of the line 100 area. When I actuated the pump after a second or 2 it sounded like a transfer truck changing gears only more quiet. When I actuate with the center console switch it is a quiet steady hum sound.
The top is stuck down and I have no one to help with moving the heavy roof to the closed position. Therefore, the trunk lift cylinder is the only cylinder that is easy to remove. Top hydraulics rebuilt it 5 years ago. So, that seal could have been fouled with stop leak. Should I send the top lift cylinder back for a rebuild?
I pulled out the trunk lift cylinder and the rod is stuck in the collapsed position. I can’t pull the rod out extended. Could this be the reason the roof is stuck down? What caused the cylinder rod to get stuck?
I shipped the trunk lid cylinder off for rebuild. IIRC I COULD ROTATE THE ROD BY TWISTING THE CLEVIS.
Do ya’ think the trunk lid lift cylinder failure kept the roof stuck down? Does the stuck cylinder explain the sound of shifting gears coming from the pump within 2 seconds of actuating using the scanner tool?
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