Need to disconnect battery to bring hardtop down.
07-17-18, 04:43 AM
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Need to disconnect battery to bring hardtop down.
Is anybody familiar with this problem on the 2002 Lexus SC 430? I'm in Iceland so I don't take the top down a lot.
But not only do I need to disconnect battery to bring hardtop down but when it's half way back (when closing) it stops. Then I need to release the button and press it again for the top to close all the way.
The bigger problem is that I need to disconnect the battery every time I take the top down.
Is anybody familiar with this?
With warm regards from Iceland.
GM
But not only do I need to disconnect battery to bring hardtop down but when it's half way back (when closing) it stops. Then I need to release the button and press it again for the top to close all the way.
The bigger problem is that I need to disconnect the battery every time I take the top down.
Is anybody familiar with this?
With warm regards from Iceland.
GM
07-17-18, 06:20 AM
#2
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That's a new problem description and workaround to me but several members have been on the SC430 forum for a lot longer than I have been on it. Hopefully someone will respond. As a pure guess it may be that some electrical component is resetting itself with battery disconnect, and then an error occurs in lowering the top (which is produces an error code) when you have to release button and restart the process. Then on the next lowering attempt the system will not initiate the lowering process because the error code (or electrical component is in "error" state) until you reset it again with battery disconnect.
Does the top go back up with no issues or does problem occur lowering as well as raising top?
Does the top go back up with no issues or does problem occur lowering as well as raising top?
Last edited by Jabberwock; 07-17-18 at 06:25 AM.
07-17-18, 07:04 AM
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That's a new problem description and workaround to me but several members have been on the SC430 forum for a lot longer than I have been on it. Hopefully someone will respond. As a pure guess it may be that some electrical component is resetting itself with battery disconnect, and then an error occurs in lowering the top (which is produces an error code) when you have to release button and restart the process. Then on the next lowering attempt the system will not initiate the lowering process because the error code (or electrical component is in "error" state) until you reset it again with battery disconnect.
Does the top go back up with no issues or does problem occur lowering as well as raising top?
Does the top go back up with no issues or does problem occur lowering as well as raising top?
My best,
GM
07-17-18, 08:37 AM
#4
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From your description Jabberwock is probably correct, there is an intermittent switch/sensor as opposed to a physical mechanical, problem that is causing a condition that stops the roof from moving. The battery disconnect resets the condition and the roof completes the close procedure.
One potential area is motor synchronization. There are sensors that read pulses from each motor (L/R) if they are not synchronized (within parameters) the roof stops. Another suspect area for this problem is the roof ECU or brain. It may not be receiving (wiring issue) or interpreting the data properly (more likely because of the battery reset).
The problem is determining which switch/sensor is the culprit, there are several. Unfortunately you will need either someone with a DTC reader/techstream software or a Lexus Service Center to get the Diagnostic Trouble Code. Codes are “active”. This means they are not stored after the car is shut off. And it may take a few cycles of the roof for an active DTC to show up on a reader. It’s also the reason your battery disconnect procedure is working.
The DTCs (B2500-2555) will point us to the suspect component area. From there we can probably provide advice on a DIY or let you know this should be handled by Lexus.
One potential area is motor synchronization. There are sensors that read pulses from each motor (L/R) if they are not synchronized (within parameters) the roof stops. Another suspect area for this problem is the roof ECU or brain. It may not be receiving (wiring issue) or interpreting the data properly (more likely because of the battery reset).
The problem is determining which switch/sensor is the culprit, there are several. Unfortunately you will need either someone with a DTC reader/techstream software or a Lexus Service Center to get the Diagnostic Trouble Code. Codes are “active”. This means they are not stored after the car is shut off. And it may take a few cycles of the roof for an active DTC to show up on a reader. It’s also the reason your battery disconnect procedure is working.
The DTCs (B2500-2555) will point us to the suspect component area. From there we can probably provide advice on a DIY or let you know this should be handled by Lexus.
Last edited by VVTiBob; 07-17-18 at 12:24 PM.
The following 2 users liked this post by VVTiBob:
DshngDaryl (07-17-18),
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