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About Dorchester

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    540i M-Sport
  1. Dorchester

    Drive Train Error Message

    I was just a little surprised that it happened with only 35,000 miles on the clock!
  2. Dorchester

    Drive Train Error Message

    Thanks for the heads up on that Andrew. I guess that we shouldn't always take what BMW tells us at face value - but perhaps I was being a little pedantic, as I didn't personally consider the swirl flaps being part of the drive train. On the other hand, I fully appreciate the fact that BMW have to make their alerts not only fool proof, but idiot proof too - and there are a few of those out there! As a footnote, my experience does clearly demonstrate the advantages of purchasing a BMW Approved vehicle, as the items on the dealers worksheet illustrates:- Replace swirl flaps = £985.20 Replace battery = £284.17 Replace C/A door handle = £455.98 I wont tell @Lennox about the battery!
  3. Dorchester

    Drive Train Error Message

    I also had the "Drive Train Error" message appear on the screen of my 2011 535d M-Sport that I acquired in June this year. Whilst waiting for the local BMW dealer to rectify it under warranty, it happened a further 2 or 3 times, but was never accompanied by the "reduced power" state as indicated on the screen. Last week the car went into the dealer, who diagnosed and replaced the swirl flaps (sticking occasionally), and since then all has been OK. I must admit that I can't see any obvious reason for this fault to trigger the Drive Train warning - now if it had been the engine warning, I could accept that. Can anyone think of any connection? They also diagnosed that the BMW battery was failing (new just before I got the car), and also that the Comfort Access driver's door handle had a fault on it which required its replacement. Both of these items are being replaced and fitted under the BMW warranty.
  4. Dorchester

    Inner lens as additional stop light

    Correct John, he can either use two separate relays, or a single DPCO (Double Pole Changeover) relay. It does mean unfortunately that he will not have to use the diodes that he has already purchased! The response time of the relay will mostly depend upon the rating of the relay and the magnetic strength of the relay coil. Most 'cheapo' type automotive relays normally tend to have a slightly longer response time of up to C. 200mS (0.2 seconds), as the coil is usually designed to operate on a voltage of between 10 - 14.5v. Further, if the relay has a high current rating of (say) 40A, then the contacts will be larger (heavier), and thus will take slightly longer to move when the relay coil is energised. A relay designed for industrial use is normally of a higher quality, and designed to operate on a specific voltage (with a normal tollerance of +/-10%). As the relay contacts are required to switch a current of less than 2A, I would suggest that a 12v.DC industrial relay with a contact rating of between 3 - 5A would be the optimal choice. So, to answer your question John; yes there would be a slight delay, but with a decent relay it is doubtful that it would be noticed by any casual observer. The delay would be less than the time it takes for the lamp fillament to to reach full luminosity after the voltage is applied!
  5. Dorchester

    Inner lens as additional stop light

    Hi Oleg, If you use a relay connected as shown in the attached diagram, you will not overload the existing brake-light switch or the existing cables supplying the brake lights, and all of the lights should be at full intensity. Don't forget to put a fuse in the cable from the relay to the battery!! Hope this helps - and good luck Rear Fogs with Brake Lights1.pdf
  6. Dorchester

    Inner lens as additional stop light

    I agree with you entirely John that if standard tungsten filament lamps are used, the total current will overload the existing cable and switch in the brake light circuit by some 50%, which apart from being undesirable, will result in an additional voltage drop. My suggestion to Oleg to try the ‘relay’ method was given “In order to rule out the resistance of the diodeâ€, which will be dependant upon the specification and current rating of the diodes used. When I originally did this modification (some years ago), I used LED lamps in the rear fogs, as this added a negligible amount of current to the brake light circuit. I did not incorporate the side (parking) lights in the modification. The Check Control however was not triggered when the brake was applied. As the relay coil presented a high resistance path to earth in the fog light circuit, this satisfied the Check Control unit when it checked the lamp filaments in the rear fog lights. It did however issue a warning when the rear fogs were switched on manually, presumably due to insufficient current being taken by the replacement LED lamps.
  7. Dorchester

    Inner lens as additional stop light

    The rear fog light dashboard warning light will illuminate when the fiog lights are switched on manually (as required by UK Law), but will NOT operate when the fog lights are used as additional brake lights. If you look at the wiring diagram, you will see that the relay connects the fog light to the brake circuit only when the realy is not energised. When the fog light is switched on manually, this energises the relay coil, and the relay disconnects the fog light from the brake light circuit, and connects it to its normal circuit which allows it to operate normally - with the dashboard warning indicator. This makes it comply with the MOT test requirements. Hope that this explanation helps.
  8. Dorchester

    Inner lens as additional stop light

    Hi Oleg, The lack of brightness could be caused by the forward resistance of the diode, and/or the additional volt drop in the existing cable feeding the brake lights. This cable is now taking two or three times the current, so the volt drop along it will be two or three times greater! In order to rule out the resistsnce of the diode, you could use a couple of relays instead. I have done this on my previous E34, and it also has the benefit that it does not light up the rear fog warning light on the dashboard when the brakes are used. Hope that this helps you solve the problem Circuit to operate Rear Fogs with Brake Lights.pdf