Flashing lights on power top switch

[KSprot]

I recently bought an 03 z4. The top was not working and now that I have it, i can manually unlock the upper lock with an allen wrench but cannot get it to lower by pulling the release in the trunk. Lights flash red and orange on the dash power top switch. What now? I am happy to DIY but unsure where to start. Thanks for any help.
Ps Love the car!

[Clearancediver]

Quarter turn counterclockwise then pull….. opposite to engage hydraulics (could be the their way around… You can google using appropriate key words). Ensure you lubricate the rollers the latch arms engage into. They need to be free rolling otherwise it will fail to open due to the resistance created….. There is an actual error message for high resistance.

When working on the car…. Disconnect the battery… the car will set error/fault codes if connections are opened (wiring) which for the most part aren’t capable of being read/cleared by handheld code scanners. BMW specific codes need to be “decoded” ie…read by INPA (old) or ISTA (ISTAD) software. I suggest you google ISTAD and download. You will need to get a switchable cable to connect the car to an old windows computer that you’ve got hanging around…or buy.

Switchable as pre facelift cars (yours) and post facelift cars have a slight wiring (two pins) difference. You need to make sure the switch is set to the pre post lift position (its obvious … don’t worry).

ISTAD has the TIS (technical instructions … repair suggestions/procedures)…and has the capability to “go down the rabbit hole” on a fault/error code to the point that it will read the resistance of a wiring. Hence my comment in the first sentences.

You should google …. Z4 convertible top issues … or similar wording to pull up posts/videos etc.

Latch rollers frozen/rusted unable to freely turn
Hydraulic oil low
Shelf in the trunk not down enough (top folds down onto it)
Shelf knobs not turned into proper position
Bulkhead switch issues (micro switch bad… silver tab missing…. ) Short/bypass to confirm
Hydraulic top motor fubbar’d … rusted out/frozen due to water damage due to drain blockage. Remove plugs on bottom of tube on the bottom of the car in the cavity (smaller hands can reach into it). You will need to clean out that tube (blow out upwards, but ensure you are ready to trap crap blowing up into the cab)…..

If you change the hydraulic/electrtic motor, move it to the trunk and ensure it’s as upright as possible. You can again google this ..

Google is your friend,, here are countless posts on all of the above….

Google … dc_wright convertible top motor procedure. Or Shipkiller’s convertible top motor procedure … might need to play with the words. Z4 convertible top motor procedure likely will pull this up as well. dc has updated Shipkiller’s original step by step guide.

If you plan on owning the car and working on it yourself… get ISTAD and use YouTube to learn how to use it.

If you get the pesky seatbelt light… read the code and if it’s high resistance … I’ll point out the specific connection in the battery well that causes it. After 8 years and countless cleaning etc to get it into the proper resistance spec…. I cut it out and wired in a new connection…..

Have fun… mind is an ‘04

[KSprot]

The adventure begins!

[Clearancediver]

Yup…. Google FCAB issues… usually easier to buy the left and right wishbones with the FCAB installed.. they also come with new ball joints. There are cheap to expensive offered on Amazon and reputable parts dealers online. Do that and change the front motor mounts at same time. Easiest time to do them as you are “there” anyway. Passenger side mount can be done afterwards but you have to thread it into the area through the little trap door that you open to get at oil pan plug…

I would also do the left/right strut/shocks on the car as well… and then get your car alignment afterwards. You now have the suspension refreshed.

All the above is DIY … except get a shop to install the front strut/shock in the strut assembly. Portable devices to do this are simply not safe and you can get seriously injured if you f..k up. The engine shop can change them out for you in under 30 minutes (you remove/replace assembly back home) and it’s the best $90 or so bucks you will ever spend. I say this as ex-military who holds various qualifications relating to high explosive/IEDs. I got to the part where everything was cranked down so I could remove the top nut to disassemble from… decided that it simply wasn’t worth getting killed…. and I love playing with explosives.

Next comes doing a valve cover gasket replacement. Get good quality replacement gaskets… remember to put a day of RTV on the transverse joints where the Vanos mates to the front of the engine block and the. 90 degree corners on the half moons on the gasket.

If you have oil leaks on the drivers side of the engine block… change/replace the oil filter housing o-ring…. Again.. these are simple DIY projects. Changing the Crankcase ventilation valve (CVV) is relatively simple and does not involve removing air intake to do so… but there is a simple trick to do so. You can DM me for that when you go to do that.

If you ever replace the water pump… there is a trick to doing that as well. You remove the nut from the drivers side motor mount and place a jack under the front of the engine (Google to find out where to do so) and then jack up gently until the threaded part of the engine mount now shifts until the threads have disappeared… The engine has now rotated sufficiently enough that the water pump can be pulled out…just missing the front transverse structural strut that otherwise blocks doing so.

The starter motor can also be replaced without removing the air intake cover. You do have to remove the various engine intake tubing. It’s a good time to remove the idle control valve and clean… as well as replacing the “air intake boot” that is known for cracking and leading to air leaks and idle issues.

Pelican Parts is a good parts supplier for those in the USA… and their technical forum has a ton of R&R articles/diagram/procedures for the DIYer.

Also… get yourself an old cheap windows laptop and download ISTAD software and get a “switchable” USB to OBEDII cable. The BMW tech software not only reads fault/error codes but provides diagnostic and repair advice. Forget portable scanners… few can read BMW proprietary error codes and even fewer can delve into the causes/diagnostic/repair procedures. You can Google ISTAD for posts and YouTube videos on how to use.

And always… disconnect the battery from the car when you intend on disconnecting cables/wiring looms. The car will set error codes that require ISTAD to clear etc. if you don’t….Anytime you do disconnect wiring/connectors.. use electrical cleaner to clean the male/female surfaces.

Think that will do for advice for now…

Ohhhh… if your radio is the Carver 10 speaker high end DSP audio system…. The radio absolutely cannot be replaced with an aftermarket radio. There were 3 radio systems that were available to be installed.

Ohhh…. Realoem.com … parts/diagrams specific to your car are available by inputting the last 7 digits of your cars VIN…..

Cheers… Steve