Right so here is the story...
I was driving to work about a week ago when the engine management light came on on my Jimny (2001 soft top). I continued to work, and forgot about it and made my way home after work. I noticed it again and also the fact that my heaters were blowing out cold air when on the hot setting... Very strange.
When i got back i had a look under the bonnet and the coolant bottle was completely empty! I checked the rad after it had cooled down and could not see the water level line inside (if any!).
I cant believe it ran out as i feel as though i checked it often enough. Anyway... i took the bottle out, and it had some gunk in the bottom of it so washed it all out and topped up with coolant and replaced. I also filled the rad up with coolant. Ran the engine for 20 minutes or so but still just cold air from the vents.
Temperature gauge is fine and sitting in the middle where it always did. Jimny is running as sweet as ever and idling well so no obvious defects so far. What im worried about is what damage i may have done and why my heaters arent working!?
There is no water in the oil as its a good clear/black colour and good level. However seems to be very minimal signs of gunk in the rad (same as what was in the coolant bottle) but not sure if this if fairly normal?
Please could someone help/advise on what may be causing the heaters to not work and/or if i have done serious damage?