2005 volkwagen golf 2.0 sdi [ac] 5 doors hatchback manual handbook

put in some iridium spark plugs and change oil and filter

Since you say gear oil I assume that it is a manual transmission. Here are codes and fluid type/capacity
Transmission fluid Capacity 2.0 liters
Transmission code: DYP, ECW, EFG, ERS, FBV, FBX, FBY, EGY, EVR, EZK, FCF Type G51 SAE 75w-90 (synthetic oil)
Transmission codes: DQY, DBZ, DZQ, DZC, EGC, EGF, EKG, EMR, EMS, ENH, ENJ, EBJ, EBP, EBQ, EZH, EWW, FBW, EGR, EBN, EGT, EGX, EGU, EHC, FDS, EHA Type G50 SAE 75w-90 (synthetic oil)

I would get a diagnostic check done on it as could be a number of things, is your engine management light on or does it come on at any point.

bypass the starter motor, see the diagrams attached, and see what happen, you will have a new vision with this.
God bless you

Volkswagen recommends replacement every 80,000 miles (tensioner pulley must also be replaced).

hi yes, you can try adjusting the striker pin that the door closes on, this might be loose or just pushed back a bit, just adjust it forward a few mill at a time then tighten it...

1993-2005 Volkswagen Jetta, Golf, GTI, Cabrio (A3-A4) Hatchback & Sedan Workshop Repair Service Manual - 350MB PDF

1993 2005 Volkswagen Jetta Golf GTI Cabrio A3 A4 Hatchback Sedan...

This is a COMPLETE Service and Repair Manual for your 1993 1994 1955 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 VW Jetta, Golf, GTI, Cabrio (1.8L turbo, 1.9L TDI and PD diesel 2.0L gasoline, 2.8 LVR6) (A3, A4 Platform) Hatchback & Sedan. It covers every single detail. All models, and all engines are included.

This QUALITY manual is 100 percents COMPLETE and INTACT, no MISSING/CORRUPT pages/sections to freak you out! Detailed illustrations, exploded diagrams, drawings and photos guide you through every service repair procedure. This manual can be viewed on any computer, as well as zoomed and printed. All repair procedures are covered A-Z. This manual for VW Jetta, Golf, GTI, Cabrio makes any repair job easy to do with very easy to follow step-by-step instructions & pictures on all areas of repair.

1993 1994 1955 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 VW Jetta, Golf, GTI, Cabrio (1.8L turbo, 1.9L TDI and PD diesel 2.0L gasoline, 2.8 LVR6) (A3, A4 Platform) Hatchback & Sedan
===========
Format: PDF
System: All Versions of Windows, Mac, iOS, BB, Android, etc..
Requirements: PDF Reader.
Printable: Yes

TABLE OF CONTENT (example)

GENERAL INFORMATION *

ENGINE *
engine mechanical
engine lubrication system
engine cooling system
engine control system
fuel system
exhaust system

TRANSMISSION/TRANSAXLE *
clutch
manual transaxle
automatic transaxle

DRIVELINE/AXLE *
front axle
rear axle

SUSPENSION *
front suspension
rear suspension
road wheels & tyres

BRAKES *
brake system
parking brake system
brake control system

STEERING *
power steering system
steering system

RESTRAINTS *
seat belts
supplemental restraint system (srs)

BODY *
body, lock & security system
glasses, window system & mirrors
roof
exterior & Interior
Instrumental panel
seat

AIR CONDITIONER *
air conditioner system

ELECTRICAL *
wiring diagrams
starting & charging system
lighting system
driver information system
wiper, washer & horn
body control system
lan system
audio visual, navigation & telephone system
auto cruise control system
power supply, ground & circuit elements

MAINTENANCE *
maintenance

INDEX *
alphabetical Index

1993 1994 1955 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 VW Jetta, Golf, GTI, Cabrio (1.8L turbo, 1.9L TDI and PD diesel 2.0L gasoline, 2.8 LVR6) (A3, A4 Platform) Hatchback & Sedan

think the heater relay timer for the glow plugs is having a heart attack and playing up ,often happens and a new one is about 90 euros and only available from the dealer normally but some motor factors will supply but they only send a lad to the dealers on a moped whilst you wait for it thinking they are having a job finding one

What colour is this light.
The Golf mk4 sdi certainly should have brake pad wear sensors front and rear and the light on dash for this is orange with a similar symbol to what you describe.
The ABS light is orange with ABS printed on it
John

drivers door latch is bad there is a module in the latch so the electric side is inop