Truck will not turn over, gauges all come on but nothing from the engine, acts like dead battery but it is brand new...it did it before and was told it was the battery, put a new one in....worked great for several days....then no start...any help would be great

no year told , no VIN, on country.told
1983 to 2011 made. (wide gulf)
South Africa? (we dont cover there)
1.8L Diesel ! bingo
a/t box or m/t tranny not told,. and matters.
but starter cranks fast?????
temp up and down means top of engine was dry of coolant, below the ECT sensor. does that.
try to be more clear as we can not hear you crank any engine, deaf.
the starter is dead or not dead.
key on , battery charged, turn to start. and the starter is dead silent, or clicks or chatters only.
if cranks fast and engine will not run over 10 seconds say that.
if only engine is dead, that has 50 causes. and we use up to 20 tools you don't have to find it and skills.
but no engine told and I don't want to make the engine worse cranking it
no crank tests are simple but not told it is....

Battery is not holding a charge great enough to start the engine, acts like it is dead. Get a new battery would be my first step.

Battery ? connections , Cables

What ever you wiggled is your next project to resolve first

could be the starter relay .

CHECK THE MAIN FUSES, ON THE FRONT,, AND THE BATTERY CABLE.... YOU CAN REQUEST A SERVICE REPAIR MANUAL FOR FREE AT BESTDIRECTORYSOLUTIONS.COM

starter cannot act good if it does not spin the engine over quickly with new battery
pull it for a bench test under load
check and clean terminals and check for good ground point

The first things you should verify ar as follows..

- Battery connections. Check if they are cleaned and tight. Also inspect the wires for corrosion or fraying.

- Fuses. Check the under hood fuse box for fuses that are burned. If you have no power to any systems in the car it may be a main fuse that is burned.

- Check that any ground connections around the fuse box are tight and free from corrosion.

if it doesnt even click over straight nothing at all ....
battery is no go at all
1.if it starts off a jump.....
altinater could be bad...take positive battery terminal off battery while car is on ...if it stays running its good if car dies altinaters bad.
2.if its good replace battery with brand new one....
3.if the cars battery is brand new and car acts like it wants to start real bad but wont...
if you have gas in the vehicle and it sounds like it dont ... your ecm is bad electronic control module or ICM ignition control module.....its the brain the spark

does it turn over?

alternator is out