Another electric roof thread

[Joss]

Hi folks, trying to work out where the smoke has escaped from the electric roof circuit? the roof started to fail by only going part way up and only going down under power from about the same point.
All brake lights are working, roof micro switch has been checked, seem to have continuity there too, I think the switch is okay - only checked continuity on the pads on the circuit board for that though. I don't hear any clicks from the relays, and no noise/heat from the motor, how do I test the relays? or for that matter where's best to stick the multimeter to get voltage readings?

Thanks

 

[gookah]

Providing oil level is correct, the switch could be failing. slightly out of position, or there could be a break in one of the 2 wires from the microswitch which only show up when the roof moves

I did a thread about getting the instrument cluster roof indicator lamp to display when all conditions are met, which would have narrowed down the location of your above issue, but it was ridiculed, saying BMW fitted it to let you know the roof was down.

The fact that it fails part way down suggests a break in the wiring in the roof microswitch or the oil level (in which case you would still hear the pump running)

 

[NZ00Z3]

trying to work out where the smoke has escaped from the electric roof circuit?

I love empirical testing and the conclusions it produces.
After a 35 year career in the electrical industry, I have to agree with you. Whenever the smoke comes out of the electrical equipment, the equipment stops working.

Go to the "Resources" section of this forum (see blue ribbon at the top of your screen). Page 1 has a couple of wiring diagrams specific to some UK Z3's. Page 2 has other wiring diagrams for the Z3. You will need to know the build date of your Z3, so you can select the correct wiring diagrams. The date range that each set of wiring diagrams covers, is on the bottom right of the first page.

The brake switch has 2 set of contacts. One for the brake lights and the other for engine computer (DME) tasks, like safety checks, cruise control operation and soft top control. So, the brake lights can still be fully functional, but the DME contact can be faulty. With a scanner, you can check the DME for fault codes. If there is a code with wording like "BTS/BLS plausibility", then this is saying that one of the brake switch contact is faulty and you have to replace the brake switch.

You've tested the micro switch, that's good work.

Another area of weakness, which may fit your problem, is that the wires that supply the micro switch travel down the left hand side of the soft top. There is a bending point at one of the joints where the wire can break inside of the insulation. It may make the circuit to begin with, but brake the circuit as the top goes down. So, test the continuity of the wires to the micro switch and back to earth by testing at the soft top switch, pin 2 of connector X13045. When the soft top stops working, test it again to see if the wiring is still good. If there is no continuity, then you have found your problem and can go searching for the wire break.

If you are still having problems, then work through the wiring diagrams for the soft top control and see what you find.

 

[Joss]

I think my labeling might be slightly off? I think what I have as 1 is actually pin 2? but - foot on the brake, ignition on, roof partially lifted (release the switch) - if I hold the up button and hopper 1 & 2 the roof goes up, the down button and iirc 5 & 1 it goes down. Not being great at electrics is guessing the hopper is either mimicking the earth connection that the roof microswitch should do or something the switch itself should do? If it helps there's continuity between or/br at the button and one side of the black wire at the roof switch?

 

[NZ00Z3]

Do you have a set of wiring diagrams?

What is the build date of your Z3?

With the above information, we can then talk turkey based on the same wiring diagrams, otherwise, it's oranges and lemons.

 

[Martin Sullivan]

FYI and in case it comes in useful, I’ve sourced and made replacement micro switches. They have a fly wire on so you can join them into the existing wiring as you please

 

[Joss]

Do you have a set of wiring diagrams?

What is the build date of your Z3?

With the above information, we can then talk turkey based on the same wiring diagrams, otherwise, it's oranges and lemons.

Thanks

It's a 51 plate car so I'm guessing (I've popped down to visit my parents for a day or two) it's build date is 2001, and I've dl'd the 2001 troubleshooting pdf - it appears to be the same as the american one I was using XD.

The wires from the roof micro switch seem to disappear in under the plastic behind the passenger seat - is there somewhere reasonably easy to get to that they reappear?

 

[NZ00Z3]

I live deep down in the South Pacific, so have no idea what a "51 plate" means.

The drawings for the soft top controller are:

• 5430.2-00
• 5430.2-01

In the 01 drawing, you'll see that the micro switch wire comes out at the convertible top switch (back of the center console) on pin 2, connector X13045.

• Multi-meter on ohms/continuity/diode testing or similar
• Unplug the switch
• Turn the "T" handle on the hydraulic pump unit in the boot/trunk a couple of turns, so you can manually move the top.
• Test from pin 2 on the top switch connector to earth. With the soft top released, there should be continuity to earth, though the micro switch.
• Manually pull back the top and put into the fully down position. The continuity of the micro-switch should always be there. If there is a break, then you have your problem.
  

 

[Steve Medlock]

FYI and in case it comes in useful, I’ve sourced and made replacement micro switches. They have a fly wire on so you can join them into the existing wiring as you please

View attachment 192965

Are you selling those Martin?

 

[Martin Sullivan]

I will be / I am.
My Z3 is at the body shop at the moment so I didn’t get the chance to do a proper “how to” or get the final photos etc

Will you be at ZedFest Steve?

 

[Steve Medlock]

I will be / I am.
My Z3 is at the body shop at the moment so I didn’t get the chance to do a proper “how to” or get the final photos etc

Will you be at ZedFest Steve?

No, I can't make Zedfest unfortunately, but would be grateful if you could put me down for one whenever they are ready please.

 

[ZEDonist UK]

@Steve Medlock

Hi Steve,

It's Martin here.

I have pretty much finalised the microswitch. I'm just waiting on a couple of little bits for it.
I have installed the new microswitch in my car and it's working nicely.

I will post a new article in the "For Sale" section for reference.

 

[ZEDonist UK]

The new microswitches.

The switch is practically identical to the original bar a slight kink here or there. The switch comes with a fly lead which gives enough length to reach behind the passengers seat. The heat shrink solder connectors then tuck into / behind the roof frame work.

I have installed one of these in my Z3. The microswitch itself was fine, I had an issue with a damaged cable around the hinge area. It only takes about 30 mins to do.