BMW Z3 (1995–2002) and Z4 (E85/E86 2002–2008, E89 2009–2016) — common faults, maintenance guides and repair tips.
The usual cause is the circuit board of the ABS unit's control module: vibration breaks the solder joints near the connector. The fault can come and g...
The OBD connector alone only reaches the engine control unit, so the airbag module codes cannot be seen from there. The other control units are read f...
About 30 mA is usually a normal draw while the car is parked. Disconnecting the negative terminal prevents the battery from draining in winter. Deep d...
Worn large rubber bushings let the subframe move, so the load goes to the rear mounting lug and the spot welds. The floor panel can come loose or the ...
Eccentric bolts alone may not be enough, because the adjustment range is small. The eccentric diameter of the E39 eccentric bolt is 33 mm and gives mo...
Usually the window guide channel has dried out or got dirty. Spray thin oil into the channel, move the glass back and forth by hand and clean the glas...
Start with the electrics. Clean the battery terminals and cable lugs, make sure the battery is in good condition and clean the mountings of the altern...
If only one door's lock does not react, the fault is often in the lock motor. Check with a multimeter whether the control voltage reaches the lock and...
The leak often comes from the seam between the rear window plastic and the fabric or from the zip, usually in heavy rain. Sealing the seam with silico...
The cause is usually worn-out rubber bushings in the seat mounting. When the bushings give way, the seat develops play. The fix is to replace the bush...
Push the plastic sleeve all the way in, and the connector comes off like a compressed-air coupling. The sleeve is not pulled up. A rusty or oxidised c...
The most common explanation is that the clutch does not fully disengage before the shift and the gearbox gears hit each other. The noise is often hear...
The cause is often soft or worn rubber bushings in the front lower control arm, which allow the rear end to move sideways and change the wheel angle. ...
Through the OBD connector the car gives access only to engine and transmission control. The airbag control unit is read separately with BMW's own diag...
On models with IBS battery monitoring, the replacement must be registered to the car, otherwise charging does not work properly. A larger battery addi...
The most common cause is the roof motor or the hydraulic pump, which is a typical fault in early Z4 models. Water gets into the motor through the drai...
The roof drain channels get blocked, so water runs onto the motor and the motor rusts. As a symptom, the roof moves slower than before and finally sto...
The fault is related to the steering column and the electric power steering. One suggested cause is insufficient lubrication of the assist unit's bear...