Heater wont work, and check engine light came on

The problem is that even if you replace fuse #2 and fuse #8 in the engine compartment, possibly restoring map lights, air conditioning, heater and radio, it is very likely some component is busted and drawing too much power through the fuses. It is possible that the bearings in the heater need oiling finally drying out after 10 years That fuse #2 handles multiple power on functions and if it is blown, you have to round up the usual suspects, i. e. test further to see just which component has truly failed..

Very low temperatures like -10 will make motor oil so thick, the engine is VERY hard to rotate. Also, the temperature will keep you battery from discharging the required amps to turn over the engine. You should use an oil warmer, and a battery heater. Also, use a lower viscosity oil.

Code 038 means the computer is getting a high voltage return in the heater circuit from the O2 sensor mounted after the catalytic converter. The O2 sensors have an internal heater to make them work as soon as you start the engine.
You would need to test the circuit to and from the sensor to find the real problem.

by 'coil light' do you mean the glow plug light? is your car diesel? do you mean the yellow light that looks like a spring?usually if it doesnt come on or stays on there is a problem with one or more of the glow/heater plugs. If you can access them check with a voltmeter that you have power supply to them all

I didnt get your entire question....Only part of it showed....But if there is no power check and be sure that all fuses are good You should check them with a test light to make sure that all are working .......I have seen them be bad without indicating buy being burnt so you really need to use a test light on fuses....Be sure ignition is fully on or running in park with emergency brake set.
check fuse's for power on both sides of fuse.Also what size engine ?

Did you replace temperature sensor on water cooling system?

Cluster at fault or poor connection to the cluster connector on the back side of it

Overheated engines can be cause by many things

Bad head gasket

Collasped radiator or heater hose
Plugged up radiator or heater core
Plugged up cooling galleries in the engine or head cylinder

Check fuses to see if there are busted ones. Then check heater plugs if good. Heater relay included in check. Engine wont fire if the air inside the chamber is cold. Then check fan belts for wear, replace if necessary.

With very little to go by here. I'd say you need to check the igniton switch, sounds like you are loosing power.

needs a new relay unit,diesel heater light i presume ??