A light on my dashboard has come on., it is a

Have the computer scanned. If you have a service engine or emissions light on then a service code has been stored in the computer and only a scan will tell you what the problem is.

dealer only its the immobilisor symbol ,try the spare key

A yellow explanation point symbol on the dashboard typically applies to the Tire Pressure Monitoring system. A thick ! inside a half drawn flat tire symbol to be complete and comes in yellow color when lit. Under normal vehicle set-up, if this indicator stays lit after the power-on selftest, you need to check your tires for any uneven pressures and adjust their pressures to correct specifications. Okay? : )

A red exclamation point inside a circle when lit indicates your parking brake is on, or your brake fluid level is low.

it sounds like the esp/asr warning lamp indicating a fault with the stability system. Is your abs lamp on too?

use a test light to determine all fuse s are properly working or look in the owners Manuel it is however possible for a light to go bad but i would check the fuses with a test light first

change the air
flow meter

The wiring is different, if your Golf had headlights with H4 bulbs then changing to high beam turns dip off. The GTi has separate dip and high lights, on high beam dip stays on (all 4 bulbs on).

this symbol points to front or rear brakes problems and should be checked out as soon as possible hope this helps.adrian

try checking the fluid levels ,brake fluid, power steering washer bottle??

everywhere i look loads of gti's are cuttin out. mine did.it would cut out for no reason and the dashboard lights would come on. changed dizzy n no joy so i found out that if i replaced my relay fuse(number 31 on ure fuses) it stopped cutting out. i got my part from vw dealer and costs £13! its never ever cut out since and that was at least 6 months ago. hope this helps.