SL/R230: Part numbers needed
#26
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2003 SL599
Bigger fish to fry. I have a code that says RVC hydraulic unit component A7/5K1 relay which I replaced or a wire shorted to ground. I replaced the roof module because I got one to try and it didn’t change and also a S117 load assist not operating. A gallon of gas and a lighter is looking pretty good right about now. I’ve been screwing with this top issue for 2 months. And ideas
#27
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I think that code is based on the RVC detecting excess current draw in the coil side of the pump relay. Are you sure that you have the correct replacement relay? Also, unplug the pump and plug 1 from the RVC module, check pin 10 on the connector side of the RVC plug for continuity to ground.
#28
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2003 SL599
#10 wire is good. As far as the Relay it’s a new one. But I switched it with a working one fro elsewhere and same. Although I did clean the connector on pump side now all I have ai S117. Load assist down not operating or has broken wire. The button light is on but it will not raise or lower. Will this effect the top operations as well
#29
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S114 is the load assist button, S117 is the load assist up/down limit switch. S114 would generally not stop roof operation, but S117 and proper actuation of the load assist cylinders is required for operation. Load assist activates as the roof lowers, sort of catches the roof and lowers it the rest of the way into the trunk. It is done seamlessly, so most people think that the load assist cylinders are only used for trunk access, but they are dual purpose. There are two codes for S117 not operating or cable break. B1264-1 is the UP switch and that wire runs from pin 2 of S117 to pin 41 of connector 1 on the RVC. B1264-17 is the DOWN switch and the wire runs from pin 3 of S117 to pin 29, connector 1 of the RVC. S117 is located just to the left of the left load assist cylinder (just in front of the roof when it is stowed).
Let me phrase this another way that might make more sense. With the load assist UP, RVC pin 1.41 should be grounded, pin 1.29 should be open. With the load assist down, RVC pin 1.29 should be grounded, pin 1.41 open. When you start to lower the roof, load assist is up (cylinders retracted) and it remains up until the roof is folded up and raised in the regular load assist position. At this point the pressure is relieved, and the cylinders extend and lower the roof into the trunk.
If you start to open the roof, the load assist is activated as soon as the pump starts, before the locks unlatch. If it is not doing that, you have a problem there and not with the limit switch. The RVC is throwing a code because the load assist is not recognized as being in the position it is supposed to be. That doesn't mean the the switch is necessarily bad, it could be the the load assist is just not in position for whatever reason.
Let me phrase this another way that might make more sense. With the load assist UP, RVC pin 1.41 should be grounded, pin 1.29 should be open. With the load assist down, RVC pin 1.29 should be grounded, pin 1.41 open. When you start to lower the roof, load assist is up (cylinders retracted) and it remains up until the roof is folded up and raised in the regular load assist position. At this point the pressure is relieved, and the cylinders extend and lower the roof into the trunk.
If you start to open the roof, the load assist is activated as soon as the pump starts, before the locks unlatch. If it is not doing that, you have a problem there and not with the limit switch. The RVC is throwing a code because the load assist is not recognized as being in the position it is supposed to be. That doesn't mean the the switch is necessarily bad, it could be the the load assist is just not in position for whatever reason.
#31
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If you open the bypass valve, it should settle down into the trunk.
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2003 SL599
Progress!!
Mike. I got the deck lid to open and close. When it comes to the top raising there’s nothing. Pump works but that’s about it. The lift assist works fine. The roll bar came up but won’t go down either. I guessing it’s something simple. What’s your recommendations
#33
First of all, don't be concerned with any of the parameters that are showing 'not identified' or 'not recognized'. This just means that that switch or condition is not 'made'. For example, if the roof is not at the windshield, S69/1 should be 'not recognized'. Also, 317 is probably reading 'in valid intermediate position', not 'invalid intermediate position'. This is a parameter that tells you the roof position as determined by the roof module. In can be closed, open, or in between (in a valid intermediate position).
Now to the problem at hand: Error code B1644-004 is a short to ground on the roof module to pump relay wire. Unplug the pump and unplug connector 1 from the RVC module. Check resistance of pin 10 on connector 1 to ground. WIS says > 30k ohms, but it really should be infinite. If it fails this test, there is a problem with the wire. If it passes, the problem is with the relay or module. You could also just unplug the relay (with pump and module still connected) and see if the code will clear. If it clears, you probably have a bad relay.
Now to the problem at hand: Error code B1644-004 is a short to ground on the roof module to pump relay wire. Unplug the pump and unplug connector 1 from the RVC module. Check resistance of pin 10 on connector 1 to ground. WIS says > 30k ohms, but it really should be infinite. If it fails this test, there is a problem with the wire. If it passes, the problem is with the relay or module. You could also just unplug the relay (with pump and module still connected) and see if the code will clear. If it clears, you probably have a bad relay.
Last edited by pazza; 04-15-2023 at 12:39 PM.
#34
First of all, don't be concerned with any of the parameters that are showing 'not identified' or 'not recognized'. This just means that that switch or condition is not 'made'. For example, if the roof is not at the windshield, S69/1 should be 'not recognized'. Also, 317 is probably reading 'in valid intermediate position', not 'invalid intermediate position'. This is a parameter that tells you the roof position as determined by the roof module. In can be closed, open, or in between (in a valid intermediate position).
Now to the problem at hand: Error code B1644-004 is a short to ground on the roof module to pump relay wire. Unplug the pump and unplug connector 1 from the RVC module. Check resistance of pin 10 on connector 1 to ground. WIS says > 30k ohms, but it really should be infinite. If it fails this test, there is a problem with the wire. If it passes, the problem is with the relay or module. You could also just unplug the relay (with pump and module still connected) and see if the code will clear. If it clears, you probably have a bad relay.
Now to the problem at hand: Error code B1644-004 is a short to ground on the roof module to pump relay wire. Unplug the pump and unplug connector 1 from the RVC module. Check resistance of pin 10 on connector 1 to ground. WIS says > 30k ohms, but it really should be infinite. If it fails this test, there is a problem with the wire. If it passes, the problem is with the relay or module. You could also just unplug the relay (with pump and module still connected) and see if the code will clear. If it clears, you probably have a bad relay.