I'm a newbie here, but have had my Z3 for a year now. I believe the previous owner had a blog on here calling it 'Cinders'.
Its been great, no real faults, until the ABS and traction control light came on, oddly just after I had jacked up the right rear to check the exhaust. So I had been convinced that I had moved the harness for the right rear ABS sensor. A battery disconnect cleared the fault for a few minutes, but now its always on.
I bought a C110 reader.
Initial code for P0500 speed signal could be erased , no problem.
It also had 14 Front Left and 41 Rear Right. But oddly 78 Battery Voltage. But the battery is 12.4 v. (Actually, come to think of it the warnings came on before i put a new battery in)
New sensors were fitted by the previous owner.
Faults cannot be erased at all.
I took the ABS ccontrol module off, just to check for corrosion. Couldn't see anything obvious. All pins look good. Put it all back together.
Now I have codes 14 and 41. But 78 has gone, replaced by 71 ABS PUMP.
The codes cannot be deleted at all. i.e it does not require driving with a lack of signal from the wheel sensors to trigger.
So.....what do you good people think? Replace the ABS control module, as a first step? Its actually cheaper than buying a sensor (for a known ok second hand one)
I really want to look inside for dry joints!