Z4 2005 3.0 yellow warning lights...

P

pete2223334

New member
Hello,

Having a bit of trouble, hoping someone can help.

I have an issue where the parking light and traction light come on yellow and stay on. After a while, and what seems to be after I drive over uneven ground, they go out again (after turning the car off and back on).

I told my garage about this at it's major service yesterday (of course as it happened the lights weren't on when it was in the garage!). He did a diagnostic check and could see absolutely nothing wrong. About 2 hrs later, guess what, he lights returned until this morning!

Having read around the forum it seems like this is a loose connection (if it was a sensor or control unit presumably it would have shown up on the diag check yesterday?

So any ideas what it might be and how to find the fault??

Cheers!!
 
Hi & welcome pete , pics of the car will be needed before information can be handed out :) its just the way it is here mate :wink:
we like to see the metal :thumbsup:
 
Sounds like a pulse/wheel rotation sensor is grubby or broken. It makes the ABS light and DTC light come on. As above if you post a pic it will help.
 
Hi, sorry, should have posted a pic. And obviously now I want to, the lights aren't showing.

So, I've shamelessly 'borrowed' another pic to show the lights hat are coming on:



Any ideas on how I might fix?!
 
There a number of causes....Weak battery, dirty connections, brake pressure sensors and wheel sensors.

First clean the wheel sensors on each wheel. They are held by a hex bolt. After removing the bolt wiggle the sensor housing to remove. Brake cleaner is great for cleaning... Just spray liberally to remove the dirt... If that doesn't fix the problem, clean the front wheel sensor connector in each wheel well. The pressure sensors on the brake master cylinder can also cause an issue... Same deal....clean the connections with electrical cleaner and blow dry. Weak battery can also cause fault indications. If the battery is weak I would replace. Clean the connector under each seat and clear the faults.

I suggest you disconnect the battery prior to cleaning connections as doing so will cause faults and unless you have the proper software to clear them.......

BmTechnic has a one click software install that comes with a cable to attach to the diagnostics port on your car. One of the software programs he supplies you with is ...INPA... With that program you can see if your connections to the wheel sensors are ok... Or if a wheel sensor is bad. Same with the pressure sensors.. You can read the actual pressure when foot is on/off the brake. No pressure.... Sensor is bad.... INPA gives you live data read outs of many things and it allows you to clear your faults.

Ohh.... If you have an after market GPS that you have wired directly to the fuze panel... It can cause a fault if it thinks the cars electronics is a "desktop" computer and tries to "connect"... Strange as it seems... That was the eventual cause of my issue. I had to put an in-line noise filter on the power supply to the GPS stop it.
 
Hi Clearancediver,

Lots of thanks for the comprehensive reply... much appreciated. It's such an annoying issue as it doesn't ever seem to happen when I'm at the garage for a service!

How do I get to the wheel sensors? Do I have to remove the wheels. Probably need some fairly basic instructions ;-)

I don't have a GPS. There aren't any faults logged when the garage had a look.. so I might try the bmtechinc software as well.

Cheers, Pete
 
Yes... You do have to remove the wheels to get enough room to a fess the back if the wheel hub to remove the wheel sensors. Not sure if Shipkillers website has instructions .... www.shipkiller.com

It has lots if other information on many subjects. www.realoem.com has parts diagram that will help you locate the sensors. They are held in by a single hex top bolt. Actually quite easy to remove. Clean seating faces and sensor body with brake cleaner.
 
You must log in or register to reply here.
Back
Top Bottom