The Unix Nerd's Domain

BMW Abbreviations

BMW addicts are just like any other bunch of nerds, we love to abbreviate things. The following list is designed to help those of you who have yet to qualify as full BMW Nerds.

Abbreviation Translation Meaning
A/C Air Conditioning Not much call for this where I live :-(
ABS Anti-lock Braking System When the ABS computer sees a wheel lock it releases the brakes for that individual wheel for a short time. This allows the wheel to keep spinning and as static friction is higher than sliding friction stopping distance should improve on most surfaces (except for powder snow and gravel).

As the wheel isn't locked it is still possible for the driver to steer out of trouble, this is ABS's biggest benefit.
ACC Active Cruise Control Uses radar to maintain safe distance from car in front, on the new Seven.
AFM Air Flow Meter Uses a vane linked to a carbon track variable resistor and a spring to measure airflow in the intake. Now replaced by the less restrictive HFM.
ASC+T Automatic Stability Control + Traction If the wheels start to slip the computer reduces the engine power.
ATF Automatic Transmission Fluid Almost all BMWs use Dexron II / III ATF, even some manual gearbox cars. BMW power steering is also filled with ATF as a rule.
CBC Corner Braking Control Adjusts the brake pressure on the rear wheels while cornering to increase stability.
DDE Digital Diesel Electronics DME for diesels.
DIS Diagnostic Information System Plugs into the engines DME for fault diagnosis.
DISA dual resonance intake system Uses a flap in the intake manifold to vary the length of the intake runners and tune performance at different engine speeds.
DIVA It's German Fully Variable length Intake Manifold as found in the new seven series.
DME Digital Motor Electronics The computer that controls the engine management. This decides when to fire the fuel injectors and ignite the spark plugs amongst other things. It is most commonly a Bosch Motronic system.
DSC Dynamic Stability Control Adjusts brake pressure and engine power if the car could skid while cornering.
EDC Electronic Damper Control Dampers are comupter controlled for comfort or sporty handling as needed.
EML Electronic Motor Load The throttle by wire system related to traction control. EML system controls the DK motor which is the electronic throttle on some engines.
ETK Electronic Teile Catalogue Parts database, see my review of the classic parts CDROM.
EWS Electronic Watchdog System Holds a changing code combination in the ignition key which talks to the immobiliser.
FIRST Fully Integrated Road Safety Technology. Smells like one the marketing guys thought up over lunch.
FFSR Factory Fitted SunRoof Not fitted as standard to most models.
FPR Fuel Pressure Regulator. Uses intake manifold vacuum to operate a pressure valve to control the fuel pressure in the fuel rail. BMWs run a fuel pressure around 3.0 bar / 44psi.
HFM Hot Film Meter Uses a temperature vs current technique to measure airflow in the intake. Less restrictive than the older AFM.
HWW Headlight Wash Wipe A handy little toy.
ICV Idle Control Valve Used to stabilise the idle by allowing extra air past the throttle body.
ISIS Intelligent Safety & Information System System for intelligent deployment of airbags, only the required airbags are deployed.
ITS Inflatable Tubular Structure Sausage shaped head protection airbag.
LSD Limited Slip Differential Forces one wheel to turn within a certain speed of the other, useful to preserve traction on poor or slippery surfaces.

This coupling is expressed as a percentage and is 25-40% on most road going BMWs. LSD is being replaced by ASC+T on many modern BMWs.
LTW LighT Weight Generally refers to the lightened version of the E36 M3.
MID Multi-Information Display LED disply showing warning messages and other data.
OBC OnBoard Computer Provides time, date, fuel consumption, speed warning limit, range left, outside temperature, immobiliser code, etc.
OBD I/II OnBoard Diagnostics Checks the cars emmissions using oxygen sensors and a catalytic converter. Mandatory for new cars in many countries.

OBD-II really made it harder to make BMW performance chips as the system is adaptive.
PAS Power Assisted Steering All the better to help you park.
PDC Park Distance Control Radar sensors in the bumper give the driver an indication of the distance to an obstacle.
RHR Rear Head Restraints A legal requirement in Germany.
SE Special Equipment Common in the UK. An SE car has an option pack which could include alloy wheels, air conditioning, OBC and sunroof at a better price than if they were added individually to a basic car. An example would be a 525i SE. The SE badge never appears on the car which would still be badged a 525i.
SI Service Indicator board The thing with five green lights in the middle of the dashboard. Tells you when the car needs a service. Service intervals vary depending on how hard the car is driven and how many cold starts it endures.
SRS Secondary Restraint System Airbag. Primary restraint system is the seatbelt. Euro airbags are half the size of US models as almost all europeans weat seat belts, it's the law.
td / tds turbo diesel The s at the end indicates an intercooler is fitted to improve performance.
tii touring international injection As in 2002tii.
TIS Technical Information System CDROM used by BMW mechanics.
TPS Throttle Position Sensor Gives a signal to the DME when the throttle is closed or wide open.
TRX It's French Michelin designed TRX tyres and they were common on 80's performance cars. See my Tyres and Wheels page for details.
TSB Technical Service Bulletin Notices sent to the dealer to identify faults found on a BMW model. Check your car's common faults here.
TU Technical Update As on the M50TU engine.
VANOS VAriable NOckenwellen Steuerungi
variable camshaft control 		Variable valve timing. Allows one or both camshafts to move up to 12.5 degrees to optimise low and high rpm power and torque.
WOT Wide Open Throttle What happens when you press the pedal to the metal.