Yesterday the missus's Z4 roof would not close fully.
I have the GapTech module which automates the roof.
It would go up half way and then stop, 30 seconds later it would try moving again and stop.
No problem opening though, just the close movement had the issue.
The red light remained flashing showing it was part way through the movement,
The roof motor is already in the boot.
Connected a meter to it
The connections each normally have +12v,
and on opening or closing, one of the 12V's is removed and replaced with an earth, allowing the motor to turn.
This process is reversed and the opposite connection goes to earth to turn the motor in the other direction
Putting a meter across 2 positives gives 0 dc reading, but this changes once one becomes earth, and then it shows either +12v, or -12v on the meter depending upon direction.
The motor would start off at +12V in conjunction with the movement, but the earth would disappear from one connection and revert back to +12v again so the meter showed 0 as the movement stopped.
It recorded 12v again shortly after with a quick movement and then stopped again.
First thing I checked was the microswitch in the boot but that was fine.
Then I removed both motor connections, and direct wired it to the battery.
went up and down no problem so it was not a motor or hydraulic fault.
Removed the GapTech module and tried again, same fault,
So I then put INPA on and saw the following errors showing on the roof module:
the outside temperature was correct,
Errors VSW 4.1 and VSW 4.2 short circuit to gnd (ground)
Each would clear, but on movement came straight back on
So I then suspected wiring harness problems.
I removed the front headlining plastics to expose the harness.
after cutting back the sleeve this is what I found:
this would explain the reason for the intermittent movement.
When the roof reached a certain point the wire would part breaking the circuit, as the roof relaxed back into the boot the connection would re-make causing it to go up an inch and stop again.
This wire must not be part of the opening circuitry, which is why it would power all the way back down.
I checked all the other wires and found this:
and lower down the harness, this is what I found near the hinge:
So I cut all 5 wires either side of both sets of damage, and spliced 5 new wires back in. soldered the joints and heat shrank individual wires, then one large heat shrink tube to remake a sleeve covering them all.
Re-assembly is just a reverse of the above procedure (to quote Haynes).
After re-soldering the GapTech back in again, all working again
Errors cleared via INPA and stayed off.
So the E85 also has it's own loom of doom
I have the GapTech module which automates the roof.
It would go up half way and then stop, 30 seconds later it would try moving again and stop.
No problem opening though, just the close movement had the issue.
The red light remained flashing showing it was part way through the movement,
The roof motor is already in the boot.
Connected a meter to it
The connections each normally have +12v,
and on opening or closing, one of the 12V's is removed and replaced with an earth, allowing the motor to turn.
This process is reversed and the opposite connection goes to earth to turn the motor in the other direction
Putting a meter across 2 positives gives 0 dc reading, but this changes once one becomes earth, and then it shows either +12v, or -12v on the meter depending upon direction.
The motor would start off at +12V in conjunction with the movement, but the earth would disappear from one connection and revert back to +12v again so the meter showed 0 as the movement stopped.
It recorded 12v again shortly after with a quick movement and then stopped again.
First thing I checked was the microswitch in the boot but that was fine.
Then I removed both motor connections, and direct wired it to the battery.
went up and down no problem so it was not a motor or hydraulic fault.
Removed the GapTech module and tried again, same fault,
So I then put INPA on and saw the following errors showing on the roof module:
the outside temperature was correct,
Errors VSW 4.1 and VSW 4.2 short circuit to gnd (ground)
Each would clear, but on movement came straight back on
So I then suspected wiring harness problems.
I removed the front headlining plastics to expose the harness.
after cutting back the sleeve this is what I found:
this would explain the reason for the intermittent movement.
When the roof reached a certain point the wire would part breaking the circuit, as the roof relaxed back into the boot the connection would re-make causing it to go up an inch and stop again.
This wire must not be part of the opening circuitry, which is why it would power all the way back down.
I checked all the other wires and found this:
and lower down the harness, this is what I found near the hinge:
So I cut all 5 wires either side of both sets of damage, and spliced 5 new wires back in. soldered the joints and heat shrank individual wires, then one large heat shrink tube to remake a sleeve covering them all.
Re-assembly is just a reverse of the above procedure (to quote Haynes).
After re-soldering the GapTech back in again, all working again
Errors cleared via INPA and stayed off.
So the E85 also has it's own loom of doom
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