Cabrio Electronics questions

[FrankM_]

Hi all,

hoping someone with a Cabrio can help me! I am trying to repair my roof control unit and found that 'R30' is burnt and 0 Ohms. It is the resistor between the lamp and GND (via D21/T2).

Can anyone with a working control box measure the value ? Looking from the back of the box it is the resisor in the right bottom part very close to the edge of the PCB.
You don't have to resolder anything, just open the box from behind and measure this one with an Ohm meter.

(Box is normally under the floorboard, labelled 911 618 313 00 or 911 618 313 01)

Many thanks !

[mysocal911]

Originally Posted by FrankM_

Hi all,

hoping someone with a Cabrio can help me! I am trying to repair my roof control unit and found that 'R30' is burnt and 0 Ohms. It is the resistor between the lamp and GND (via D21/T2).

Can anyone with a working control box measure the value ? Looking from the back of the box it is the resisor in the right bottom part very close to the edge of the PCB.
You don't have to resolder anything, just open the box from behind and measure this one with an Ohm meter.

(Box is normally under the floorboard, labelled 911 618 313 00 or 911 618 313 01)

Many thanks !

It's 10 ohms, only used as the fault light current limiting resistor.
The top cover is for a 964 cab top ECU, and not for the ECU electronics (911 3.2) you have.
Read here for cab top info under Porsche Cab Top; https://www.systemsc.com/problems.htm

The typical cab top ECU repair only takes about 10-15 minutes. No need to remove relays, they never fail!

[FrankM_]

Thanks,

I'll replace the 10 Ohms but something tells me that's not gonna be the end of it.
Is there a good test of this box outside of the car ?

Going from the wiring diagram :

+12V on 30, 15
GND on 31
a bi-directional LED with resistor between MS/MO, MVR/MER and MVL/MEL to check motor activations
GND on ZR and ZL to simulate roof closed (initially)
0 : not connectected since 'roof up' is simulated (initially)

SL and SR : open (not GND) ?

But then : I, L ?

L -> to a 1.2W dash light -> to 12V -> to A (open) or Z (closed) to simulate the putton presses
Do I need a signal on I ?

Thanks in advance for any pointers

Frank